user: You are a structured reasoning expert tasked with solving problems step by step. 
You first think about the reasoning process in the mind and then provide the answer. The reasoning process and answer should be enclosed within <think> </think> and <answer> </answer> tags, respectively, i.e., <think> reasoning process here </think> <answer> answer here </answer>. 
Given a question and the associated knowledge graph triplets (entity, relation, entity), you are asked to answer the question with these triplets and your own knowledge. 
You can break down the original question into several sub-questions and explore the given knowledge graph to solve them step-by-step. If there are multiple possible answers, choose one as the final answer. 
After thinking, when you finally reach a conclusion, clearly state the answer within <answer> </answer> tags, i.e., <answer> answer here </answer>. 
Question: what did general robert e lee die from? 
Knowledge Triplets: Robert E. Lee, military.military_person.participated_in_conflicts, Battle of Chancellorsville
Robert E. Lee, people.person.parents, Henry Lee III
The maxims of Robert E. Lee for young gentlemen, book.written_work.author, Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.04zc_73
General Lee, common.topic.article, m.09rp7g
Arlington House, The Robert E. Lee Memorial, location.location.containedby, Virginia
m.0gx4xcj, military.military_command.military_commander, Robert E. Lee
The wit and wisdom of Robert E. Lee, common.topic.notable_types, Book
m.04fvbbv, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.04fv8cn
The wit and wisdom of Robert E. Lee, common.topic.notable_for, g.1256d4jd8
Robert E. Lee, military.military_commander.military_commands, m.04fv8sm
Arlington House, The Robert E. Lee Memorial, common.topic.image, Arlington House front view
Third Battle of Petersburg, base.culturalevent.event.entity_involved, Robert E. Lee
Robert E. Lee, people.person.profession, Soldier
general george brinton mcclellan fought robert edward lee, base.kwebbase.kwconnection.relation, fought
m.0h400yy, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.049y372
Robert E. Lee, military.military_commander.military_commands, m.0gvzjkp
Robert E. Lee, military.military_commander.military_commands, m.04fvgcw
Robert E. Lee, book.author.works_written, The wit and wisdom of Robert E. Lee
Robert E. Lee, symbols.name_source.namesakes, 3155 Lee
m.04fvbg9, military.military_command.military_commander, Robert E. Lee
The education of a man is never complete until he dies., media_common.quotation.author, Robert E. Lee
Robert Edward Lee, common.topic.notable_for, g.1257mzk_0
Robert E. Lee, base.kwebbase.kwtopic.has_sentences, He tightened command and discipline, improved morale and applied his principles of concentrating force and seizing the initiative.
Robert E. Lee, military.military_person.participated_in_conflicts, American Civil War
Robert E. Lee, military.military_commander.military_commands, m.04fs5_4
m.04fv8sm, military.military_command.military_commander, Robert E. Lee
Robert E. Lee's Civil War, book.book.genre, Non-fiction
The wartime papers of R.E. Lee, book.written_work.author, Robert E. Lee
Reading the Man: A Portrait of Robert E. Lee Through His Private Letters, book.written_work.subjects, History
m.0h6h_7z, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, base.kwebbase.kwtopic.connections_from, robert edward lee fought ulysses simpson grant
USS Robert E. Lee, common.topic.notable_for, g.125fy1mh_
Robert E. Lee, people.person.places_lived, m.03pl0bp
Robert E. Lee, military.military_commander.military_commands, m.04fv885
Robert E. Lee, people.person.education, m.04hxfwl
Robert E. Lee, book.book_subject.works, Uncertain Glory: Lee's Generalship Re-Examined
Robert Edward Lee, fictional_universe.fictional_character.based_on, Robert E. Lee
Robert E. Lee, fictional_universe.person_in_fiction.representations_in_fiction, Gen. Robert E. Lee
Robert Lee, common.topic.article, m.0__57
Robert E. Lee, book.book_subject.works, General Lee's Army
Robert E. Lee's Civil War, book.written_work.subjects, Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.04m2rvv
Robert E. Lee, people.person.nationality, Confederate States of America
Robert E. Lee, military.military_person.service, m.012z83yv
Robert E. Lee, people.person.quotations, Let the tent be struck.
Robert E. Lee, base.kwebbase.kwtopic.has_sentences, Lee himself was physically declining and frequently ill.
Robert E. Lee, common.topic.notable_for, g.1256fndfq
Robert E. Lee, people.person.children, Anne Carter Lee
Robert E. Lee, people.person.sibling_s, m.0w4gc9q
Robert E. Lee, military.military_person.participated_in_conflicts, Mexican–American War
m.04ywph6, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, base.kwebbase.kwtopic.connections_to, helen keller descendant of robert edward lee
The story of Robert E. Lee, book.written_work.author, Robert E. Lee
Uncertain Glory: Lee's Generalship Re-Examined, book.written_work.subjects, Robert E. Lee
m.09xmb3r, common.webpage.topic, General Lee
The story of Robert E. Lee, common.topic.notable_types, Book
general george brinton mcclellan fought robert edward lee, base.kwebbase.kwconnection.other, Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.05t5rj7
Robert E. Lee, people.person.children, William Henry Fitzhugh Lee
Robert E. Lee, military.military_commander.military_commands, m.04fvgp8
Robert E. Lee, Jr., people.person.profession, Planter
Robert E. Lee, military.military_commander.military_commands, m.04fv7qj
The maxims of Robert E. Lee for young gentlemen, common.topic.notable_types, Book
The wartime papers of R.E. Lee, common.topic.notable_types, Book
Robert E. Lee, people.person.nationality, United States of America
Robert E. Lee, military.military_commander.military_commands, m.05npp01
Robert E. Lee, Jr., people.family_member.family, Lee family
General Lee, common.topic.image, 1969 Dodge Charger General Lee
Robert E. Lee, military.military_commander.military_commands, m.04fv9ft
Arlington House, The Robert E. Lee Memorial, symbols.namesake.named_after, Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.0h400yy
On 28th September 1870, Lee suffered what was probably a heart attack and died at daybreak on 12th October., base.kwebbase.kwsentence.dates, m.0c175q6
General Lee, symbols.namesake.named_after, Robert E. Lee
m.0gx84g8, military.military_command.military_commander, Robert E. Lee
On 28th September 1870, Lee suffered what was probably a heart attack and died at daybreak on 12th October., base.kwebbase.kwsentence.kwtopic, Robert E. Lee
Robert E. Lee, Jr., common.topic.article, m.02qh0r0
Robert E. Lee, military.military_commander.military_commands, m.0w5rz8p
Robert E. Lee, people.person.quotations, The devil's name is dullness.
Robert E. Lee, Jr., people.person.gender, Male
The wartime papers of R.E. Lee, common.topic.notable_for, g.1254_dy2b
He tightened command and discipline, improved morale and applied his principles of concentrating force and seizing the initiative., base.kwebbase.kwsentence.previous_sentence, Within three weeks Lee had organized Confederate troops into what became the famed Army of Northern Virginia.
Gen. Robert E. Lee, fictional_universe.fictional_character.based_on, Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.04fvgdv
robert edward lee fought general george brinton mcclellan, base.kwebbase.kwconnection.subject, Robert E. Lee
m.04fvgft, military.military_command.military_commander, Robert E. Lee
The maxims of Robert E. Lee for young gentlemen, common.topic.notable_for, g.125fljp0m
m.012z83yv, military.military_service.military_person, Robert E. Lee
Henry Lee III, people.person.children, Robert E. Lee
Robert Edward Lee, common.image.appears_in_topic_gallery, Robert E. Lee
Robert E. Lee, Jr., common.topic.notable_types, Author
Gen. Robert E. Lee, tv.tv_character.appeared_in_tv_episodes, m.010_f229
Robert E. Lee, base.kwebbase.kwtopic.connections_from, robert edward lee captured john brown
m.04m2rvv, military.military_command.military_commander, Robert E. Lee
Robert E. Lee's Civil War, book.written_work.subjects, American Civil War
robert edward lee fought ulysses simpson grant, base.kwebbase.kwconnection.sentence, In May 1864, a newly appointed Union commanding general Grant, drove against the Confederate forces.
m.010_f229, tv.tv_guest_role.character, Gen. Robert E. Lee
On 28th September 1870, Lee suffered what was probably a heart attack and died at daybreak on 12th October., base.kwebbase.kwsentence.dates, m.0c175q0
Robert E. Lee, Jr., people.person.profession, Businessperson
On 28th September 1870, Lee suffered what was probably a heart attack and died at daybreak on 12th October., base.kwebbase.kwsentence.previous_sentence, Lee succeeded in restoring the college as a model for higher education in the South.
Battle of Fredericksburg, base.culturalevent.event.entity_involved, Robert E. Lee
Robert E. Lee, base.kwebbase.kwtopic.has_sentences, In May 1864, a newly appointed Union commanding general Grant, drove against the Confederate forces.
Robert E. Lee, military.military_commander.military_commands, m.0c05jvk
m.04fv7qj, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, common.topic.article, m.06f5v
William Henry Fitzhugh Lee, people.person.place_of_birth, Arlington House, The Robert E. Lee Memorial
m.04fv9ft, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, freebase.valuenotation.is_reviewed, Place of death
General Lee, common.topic.webpage, m.09xmb3r
Arlington House, The Robert E. Lee Memorial, common.topic.article, m.06z8ff
“It is well that war is so terrible – otherwise we would grow too fond of it.”, media_common.quotation.author, Robert E. Lee
Robert Edward Lee, common.topic.article, m.0h0tz3h
Robert E. Lee, military.military_commander.military_commands, m.04yxf4y
Robert E. Lee, military.military_commander.military_commands, m.0h1l91r
Robert E. Lee, Jr., people.person.profession, Soldier
m.04fvbh3, military.military_command.military_commander, Robert E. Lee
Robert E. Lee's Civil War, common.topic.article, m.07471hk
Robert E. Lee, base.kwebbase.kwtopic.connections_from, robert edward lee fought general george brinton mcclellan
ulysses simpson grant defeated robert edward lee, base.kwebbase.kwconnection.other, Robert E. Lee
Battle of Chancellorsville, military.military_conflict.military_personnel_involved, Robert E. Lee
There, Lee courted Custis' daughter, Mary Anne Randolph Custis, whom he was to marry two years later., base.kwebbase.kwsentence.kwtopic, Robert E. Lee
m.04yxf4y, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.062tpcg
Robert E. Lee, book.book_subject.works, Robert E. Lee's Civil War
Robert E. Lee, military.military_commander.military_commands, m.04fvbh3
Robert E. Lee, military.military_commander.military_commands, m.0h6h_7z
Robert E. Lee, fictional_universe.person_in_fiction.representations_in_fiction, Robert Edward Lee
m.04fvg8c, military.military_command.military_commander, Robert E. Lee
m.07y5lpg, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, people.person.quotations, Never do a wrong thing to make a friend or to keep one.
Robert E. Lee, Jr., people.person.sibling_s, m.0bfp0t_
Robert E. Lee's Civil War, book.written_work.author, Bevin Alexander
Robert Edward Lee, book.book_character.appears_in_book, The Killer Angels: A Novel of the Civil War
Robert E. Lee, book.author.works_written, The story of Robert E. Lee
In 1825, Lee entered the US Military Academy at West Point., base.kwebbase.kwsentence.kwtopic, Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.0gx84g8
Robert E. Lee, military.military_commander.military_commands, m.04fvn_d
USS Robert E. Lee, common.topic.image, USS Robert E. Lee (SSBN-601)
Robert E. Lee's Civil War, common.topic.notable_types, Book
m.04fvgcw, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.049y352
Robert Edward Lee, common.topic.article, m.0hn0z3g
Robert E. Lee, base.kwebbase.kwtopic.connections_to, ulysses simpson grant defeated robert edward lee
Robert E. Lee, Jr., people.person.place_of_birth, United States of America
Reading the Man: A Portrait of Robert E. Lee Through His Private Letters, book.written_work.subjects, Confederate States of America
Henry Lee III, book.author.works_written, Funeral oration on the death of General Washington
The character & faith of Robert E. Lee, common.topic.notable_types, Book
Robert E. Lee, people.family_member.family, Lee family
Within three weeks Lee had organized Confederate troops into what became the famed Army of Northern Virginia., base.kwebbase.kwsentence.next_sentence, He tightened command and discipline, improved morale and applied his principles of concentrating force and seizing the initiative.
m.04fvgx7, military.military_command.military_commander, Robert E. Lee
Battle of Cold Harbor, base.culturalevent.event.entity_involved, Robert E. Lee
Grant and Lee in War and Peace, exhibitions.exhibition.subjects, Robert E. Lee
m.049y352, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, base.kwebbase.kwtopic.has_sentences, Lee could only place his starving men in defensive lines in front of Petersburg and Richmond.
Robert E. Lee, Jr., people.person.places_lived, m.03pk_n0
Reading the Man: A Portrait of Robert E. Lee Through His Private Letters, common.topic.notable_types, Book
m.0h1l91r, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, book.author.works_written, \"To Markie\"
Robert E. Lee, book.author.works_written, The character & faith of Robert E. Lee
Robert Edward Lee, common.topic.image, Robert Edward Lee
Robert E. Lee, common.topic.image, Robert Edward Lee
m.04fv8cn, military.military_command.military_commander, Robert E. Lee
m.04fvgp8, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, military.military_person.service, m.0gllvhm
Confederate States of America, book.book_subject.works, Reading the Man: A Portrait of Robert E. Lee Through His Private Letters
Robert E. Lee, symbols.name_source.namesakes, Robert Lee
Robert E. Lee, base.kwebbase.kwtopic.has_sentences, In May 1852, he was made superintendent of West Point, where he stayed until March 1855.
Lee succeeded in restoring the college as a model for higher education in the South., base.kwebbase.kwsentence.next_sentence, On 28th September 1870, Lee suffered what was probably a heart attack and died at daybreak on 12th October.
Robert E. Lee, people.person.place_of_birth, Stratford Hall
Robert E. Lee, Jr., people.deceased_person.place_of_burial, Lee Chapel
Battle of Gettysburg, base.culturalevent.event.entity_involved, Robert E. Lee
m.0gllvhm, military.military_service.military_person, Robert E. Lee
George B. McClellan, base.kwebbase.kwtopic.connections_to, robert edward lee fought general george brinton mcclellan
m.062vc3l, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, base.kwebbase.kwtopic.connections_from, robert edward lee was president of washington college
Robert E. Lee, military.military_commander.military_commands, m.0dl56tp
Robert E. Lee, people.person.children, Mary Custis Lee
Robert E. Lee, people.person.children, Robert E. Lee, Jr.
m.04fv885, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.04yv3f8
Robert E. Lee, military.military_person.service, m.09rqqxz
Robert E. Lee, Jr., people.person.profession, Writer
Robert E. Lee, people.person.parents, Anne Hill Carter Lee
General Lee's Army, book.written_work.subjects, American Civil War
Lee family, people.family.members, Robert E. Lee, Jr.
General Lee, common.topic.notable_for, g.1yh9sw7cy
Robert E. Lee, Jr., people.person.sibling_s, m.0bfp0v5
m.049y372, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, base.kwebbase.kwtopic.has_sentences, On 28th September 1870, Lee suffered what was probably a heart attack and died at daybreak on 12th October.
Uncertain Glory: Lee's Generalship Re-Examined, common.topic.notable_for, g.125fs0sd6
robert edward lee military adviser to jefferson davis, base.kwebbase.kwconnection.subject, Robert E. Lee
Gen. Robert E. Lee, common.topic.notable_for, g.1q6783jwv
Robert E. Lee, military.military_commander.military_commands, m.04fvg8c
m.04yv3f8, military.military_command.military_commander, Robert E. Lee
robert edward lee fought ulysses simpson grant, base.kwebbase.kwconnection.subject, Robert E. Lee
Robert E. Lee, symbols.name_source.namesakes, Arlington House, The Robert E. Lee Memorial
m.062tpcg, military.military_command.military_commander, Robert E. Lee
m.010_f0tn, tv.tv_guest_role.character, Gen. Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.062vc3l
William Henry Fitzhugh Lee, people.person.parents, Robert E. Lee
m.05npp01, military.military_command.military_commander, Robert E. Lee
m.04ytrkx, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.04fvgx7
Lee could only place his starving men in defensive lines in front of Petersburg and Richmond., base.kwebbase.kwsentence.previous_sentence, Lee himself was physically declining and frequently ill.
Uncertain Glory: Lee's Generalship Re-Examined, book.book.genre, Non-fiction
Uncertain Glory: Lee's Generalship Re-Examined, book.written_work.author, John D. McKenzie
m.03pl0bp, people.place_lived.person, Robert E. Lee
Lee Chapel, people.place_of_interment.interred_here, Robert E. Lee, Jr.
m.09rqqxz, military.military_service.military_person, Robert E. Lee
Robert E. Lee, book.author.works_written, The wartime papers of R.E. Lee
Robert E. Lee, base.kwebbase.kwtopic.connections_to, general george brinton mcclellan fought robert edward lee
Reading the Man: A Portrait of Robert E. Lee Through His Private Letters, book.written_work.subjects, United States of America
Robert E. Lee, base.kwebbase.kwtopic.has_sentences, Within three weeks Lee had organized Confederate troops into what became the famed Army of Northern Virginia.
The story of Robert E. Lee, common.topic.notable_for, g.125d12whl
Robert E. Lee, military.military_commander.military_commands, m.0gx4xcj
In May 1852, he was made superintendent of West Point, where he stayed until March 1855., base.kwebbase.kwsentence.kwtopic, Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.04ytrkx
m.062trlw, military.military_command.military_commander, Robert E. Lee
Lee himself was physically declining and frequently ill., base.kwebbase.kwsentence.next_sentence, Lee could only place his starving men in defensive lines in front of Petersburg and Richmond.
Robert E. Lee, people.person.gender, Male
Robert E. Lee, people.person.places_lived, m.0105lz78
Arlington House, The Robert E. Lee Memorial, common.topic.notable_for, g.1258hf820
Robert Lee, common.topic.notable_for, g.12589bj7x
Robert E. Lee, military.military_commander.military_commands, m.049y3bl
Arlington House, The Robert E. Lee Memorial, location.location.containedby, Arlington County
He tightened command and discipline, improved morale and applied his principles of concentrating force and seizing the initiative., base.kwebbase.kwsentence.kwtopic, Robert E. Lee
m.0105lz78, people.place_lived.person, Robert E. Lee
m.0gvzjkp, military.military_command.military_commander, Robert E. Lee
general george brinton mcclellan fought robert edward lee, base.kwebbase.kwconnection.subject, George B. McClellan
In May 1864, a newly appointed Union commanding general Grant, drove against the Confederate forces., base.kwebbase.kwsentence.contains_connections, robert edward lee fought ulysses simpson grant
m.04zc_73, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, military.military_commander.military_commands, m.04fvbbv
Robert E. Lee, military.military_commander.military_commands, m.04fvbg9
robert edward lee was president of washington college, base.kwebbase.kwconnection.subject, Robert E. Lee
The character & faith of Robert E. Lee, common.topic.notable_for, g.1259m98yl
m.05t5rj7, military.military_command.military_commander, Robert E. Lee
Within three weeks Lee had organized Confederate troops into what became the famed Army of Northern Virginia., base.kwebbase.kwsentence.kwtopic, Robert E. Lee
Robert E. Lee's Civil War, book.book.editions, Robert E. Lee's Civil War
Robert E. Lee, people.person.quotations, Wisdom is nothing more than healed pain.
In May 1864, a newly appointed Union commanding general Grant, drove against the Confederate forces., base.kwebbase.kwsentence.kwtopic, Robert E. Lee
Robert E. Lee, Jr., people.person.parents, Mary Anna Custis Lee
Robert E. Lee, base.kwebbase.kwtopic.has_sentences, In 1825, Lee entered the US Military Academy at West Point.
m.0c05jvk, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, book.author.works_written, The maxims of Robert E. Lee for young gentlemen
m.04fvn_d, military.military_command.military_commander, Robert E. Lee
m.0dl56tp, military.military_command.military_commander, Robert E. Lee
Robert Edward Lee, book.book_character.appears_in_book, Gods and Generals
m.0w5rz8p, military.military_command.military_commander, Robert E. Lee
Robert Edward Lee, common.topic.article, m.0hp1wp3
Uncertain Glory: Lee's Generalship Re-Examined, common.topic.article, m.0703gbd
Robert Edward Lee, common.topic.article, m.0j72dc1
Reading the Man: A Portrait of Robert E. Lee Through His Private Letters, book.written_work.subjects, American Civil War
Arlington House, The Robert E. Lee Memorial, base.usnris.nris_listing.significance_level, National
The wit and wisdom of Robert E. Lee, book.written_work.author, Robert E. Lee
Gen. Robert E. Lee, fictional_universe.fictional_character.gender, Male
Robert E. Lee, base.kwebbase.kwtopic.connections_from, robert edward lee military adviser to jefferson davis
The character & faith of Robert E. Lee, book.written_work.author, Robert E. Lee
Robert E. Lee, exhibitions.exhibition_subject.exhibitions_created_about_this_subject, Grant and Lee in War and Peace
Robert E. Lee, military.military_commander.military_commands, m.07y5lpg
m.0w5qbtr, military.military_command.military_commander, Robert E. Lee
Lee could only place his starving men in defensive lines in front of Petersburg and Richmond., base.kwebbase.kwsentence.kwtopic, Robert E. Lee
Robert E. Lee, symbols.name_source.namesakes, General Lee
m.03pk_n0, people.place_lived.person, Robert E. Lee, Jr.
Robert E. Lee, people.deceased_person.place_of_death, Lexington city
m.07y5lq8, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, Jr., people.person.parents, Robert E. Lee
USS Robert E. Lee, common.topic.article, m.024mkb
Robert E. Lee, base.kwebbase.kwtopic.has_sentences, Lee succeeded in restoring the college as a model for higher education in the South.
Robert E. Lee, freebase.valuenotation.is_reviewed, Date of death
m.04fs5_4, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, Jr., common.topic.notable_for, g.12582464m
general george brinton mcclellan fought robert edward lee, base.kwebbase.kwconnection.sentence, Johnston was wounded in the fight and replaced by the more aggressive Lee.
Robert E. Lee, military.military_commander.military_commands, m.07y5lq8
Robert E. Lee, base.kwebbase.kwtopic.connections_from, robert edward lee descendant was helen keller
American Civil War, base.culturalevent.event.entity_involved, Robert E. Lee
Robert E. Lee, people.person.spouse_s, m.0bfp0t3
Robert E. Lee, people.person.quotations, The education of a man is never complete until he dies.
Robert E. Lee, people.person.religion, Episcopal Church
m.04fvgdv, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, people.person.quotations, “It is well that war is so terrible – otherwise we would grow too fond of it.”
Robert E. Lee, people.deceased_person.cause_of_death, Pneumonia
Robert E. Lee, people.person.children, Eleanor Agnes Lee
Robert E. Lee, military.military_commander.military_commands, m.062trlw
Gen. Robert E. Lee, common.topic.notable_types, TV Character
Robert E. Lee, Jr., people.person.education, m.0n1lycq
robert edward lee fought general george brinton mcclellan, base.kwebbase.kwconnection.other, George B. McClellan
robert edward lee fought general george brinton mcclellan, base.kwebbase.kwconnection.relation, fought
George Washington Custis Lee, people.person.parents, Robert E. Lee
Bevin Alexander, book.author.works_written, Robert E. Lee's Civil War
m.0c058rz, military.military_command.military_commander, Robert E. Lee
Army of Northern Virginia, common.topic.image, General Robert E. Lee, commander of the Army of Northern Virginia
Robert E. Lee, people.person.children, George Washington Custis Lee
Gen. Robert E. Lee, tv.tv_character.appeared_in_tv_episodes, m.010_f0tn
Robert E. Lee, military.military_commander.military_commands, m.048z_8v
Robert E. Lee, people.person.children, Mildred Childe Lee
Robert E. Lee, military.military_commander.military_commands, m.04ywph6
m.048z_8v, military.military_command.military_commander, Robert E. Lee
Second Battle of Petersburg, base.culturalevent.event.entity_involved, Robert E. Lee
George B. McClellan, base.kwebbase.kwtopic.connections_from, general george brinton mcclellan fought robert edward lee
robert edward lee descendant was helen keller, base.kwebbase.kwconnection.subject, Robert E. Lee
Arlington House, The Robert E. Lee Memorial, common.topic.image, Arlington House pre-1861
Robert E. Lee, Jr., people.person.nationality, United States of America
Robert E. Lee, military.military_commander.military_commands, m.0w5qbtr
Robert E. Lee, common.topic.notable_types, Military Commander
General Lee's Army, book.book.editions, General Lee's Army: From Victory to Collapse
Robert E. Lee's Civil War, common.topic.notable_for, g.125bc_q1k
Robert E. Lee, military.military_commander.military_commands, m.0c058rz
robert edward lee captured john brown, base.kwebbase.kwconnection.subject, Robert E. Lee
Lee himself was physically declining and frequently ill., base.kwebbase.kwsentence.kwtopic, Robert E. Lee
General Lee's Army, book.written_work.subjects, Robert E. Lee
Robert E. Lee, people.deceased_person.cause_of_death, Pneumonia
Robert E. Lee, people.person.quotations, I like whiskey. I always did, and that is why I never drink it.
m.049y3bl, military.military_command.military_commander, Robert E. Lee
Robert E. Lee, Jr., book.author.works_written, Petition of the heirs of George Washington
Robert E. Lee, military.military_commander.military_commands, m.04fvgft
Robert E. Lee, base.kwebbase.kwtopic.connections_to, john brown captured by robert edward lee
Robert E. Lee, base.kwebbase.kwtopic.has_sentences, There, Lee courted Custis' daughter, Mary Anne Randolph Custis, whom he was to marry two years later.

Answer: Pneumonia