Question: Who is the father of the only U.S. President whose grandfather was also President?

full_context: Document 1: Benjamin Harrison (bust): Benjamin Harrison is a bust by American artist Richard Peglow, located in the north atrium on the second floor of the Indiana Statehouse, which is in Indianapolis, Indiana, United States. The bust is cast in bronze and depicts President Benjamin Harrison. The bust is placed in front of a grey and black marble shield with six stars tracing around the edge of the shape. The bust and shield are approximately wide by high and has a depth of . The artwork was cast and placed in the statehouse in 2008 in accordance with Indiana code Section 2. IC 4-20.5-6-12.
Document 2: Andrew Johnson National Historic Site: The cemetery also includes the interments of Johnson's wife, Eliza McCardle Johnson, and son Brigadier General Robert Johnson Henderson. David T. Patterson, a United States Senator from Tennessee, and his son Andrew J. Patterson, who was instrumental in securing historic designation for the Greeneville properties associated with Andrew Johnson, were among others buried in the cemetery. The site was authorized by Congress as a U.S. National Monument in 1935, established on April 27, 1942, and redesignated a National Historic Site on December 11, 1963.
Document 3: Thomas A. Hendricks Monument: The Thomas A. Hendricks Monument is a public artwork by American artist Richard Henry Park and is located on the southeast corner of the Indiana Statehouse grounds in Indianapolis, Indiana. The monument is a tribute to Thomas A. Hendricks (September 7, 1819November 25, 1885), the 21st Vice President of the United States (serving with Grover Cleveland). Hendricks was a former U.S. Representative and U.S. Senator from Indiana. He was the 16th Governor of Indiana and led the campaign to build the Indiana Statehouse.
Document 4: Benjamin Harrison: Benjamin Harrison (August 20, 1833 -- March 13, 1901) was an American politician and lawyer who served as the 23rd President of the United States from 1889 to 1893. He was a grandson of the ninth president, William Henry Harrison, creating the only grandfather - grandson duo to have held the office. He was also the great - grandson of Benjamin Harrison V, a founding father. Before ascending to the presidency, Harrison established himself as a prominent local attorney, Presbyterian church leader, and politician in Indianapolis, Indiana. During the American Civil War, he served in the Union Army as a colonel, and was confirmed by the U.S. Senate as a brevet brigadier general of volunteers in 1865. Harrison unsuccessfully ran for governor of Indiana in 1876. The Indiana General Assembly elected Harrison to a six - year term in the U.S. Senate, where he served from 1881 to 1887.
Document 5: William Henry Harrison Tomb State Memorial: The William Henry Harrison Tomb State Memorial is the final resting place of William Henry Harrison, ninth President of the United States; his wife Anna Harrison; and his son John Scott Harrison, Representative and father of the twenty-third President, Benjamin Harrison. It is located on Brower Road approximately one-half mile west of U.S. Route 50 in North Bend, Ohio.
Document 6: William Henry Harrison: William Henry Harrison Sr. (February 9, 1773 -- April 4, 1841) was an American military officer, a principal contributor in the War of 1812, and the ninth president of the United States (1841). He was the last president born before the American Revolution, and died of pneumonia just 31 days into his term, thereby serving the shortest tenure in United States presidential history. He was the first president to die in office, and his death sparked a brief constitutional crisis. Its resolution left unsettled Constitutional questions as to the presidential line of succession until the passage of the Twenty - fifth Amendment to the United States Constitution in 1967. Harrison was a son of Founding Father Benjamin Harrison V and the paternal grandfather of Benjamin Harrison, the 23rd United States President (1889 -- 1893).
Document 7: Richmond, Virginia: Other historical points of interest include St. John's Church, the site of Patrick Henry's famous "Give me liberty or give me death" speech, and the Edgar Allan Poe Museum, features many of his writings and other artifacts of his life, particularly when he lived in the city as a child, a student, and a successful writer. The John Marshall House, the home of the former Chief Justice of the United States, is also located downtown and features many of his writings and objects from his life. Hollywood Cemetery is the burial grounds of two U.S. Presidents as well as many Civil War officers and soldiers.
Document 8: Samuel P. Bush: Samuel Prescott Bush (October 4, 1863 – February 8, 1948) was an American businessman and industrialist. He was the patriarch of the Bush political family. He was the father of U.S. Senator Prescott Bush, grandfather of former U.S. President George H. W. Bush, and great-grandfather of former U.S. President George W. Bush and Florida Governor Jeb Bush.
Document 9: Mary Harrison McKee: Mary Scott Harrison McKee (April 3, 1858 – October 28, 1930) was the only daughter of President Benjamin Harrison and his wife Caroline Scott Harrison. After her mother died in 1892, McKee served as her father's "de facto" First Lady for the remainder of his term.
Document 10: Ulysses S. Grant Jr.: Ulysses Simpson "Buck" Grant Jr. (July 22, 1852 – September 25, 1929) was an American attorney and entrepreneur. He was the second son of President Ulysses S. Grant.
Document 11: Benjamin Harrison IV: Benjamin Harrison IV (1693 – July 12, 1745) was an American Virginia planter, politician, and Member of the Virginia House of Burgesses. He was the son of Benjamin Harrison III and the father of Benjamin Harrison V, who was a signer of the Declaration of Independence and the fifth governor of Virginia. Harrison built the homestead of Berkeley Plantation, which is believed to be the oldest three-story brick mansion in Virginia and is the ancestral home to two presidents: his grandson William Henry Harrison, and his great-great-grandson Benjamin Harrison. The Harrison family and the Carter family were both powerful families in Virginia, and they were united when Harrison married Anne Carter, the daughter of Robert "King" Carter. His family also forged ties to the Randolph family, as four of his children married four grandchildren of William Randolph I.
Document 12: Richard Benjamin Harrison: Harrison died on June 25, 2018, after a battle with Parkinson's disease. His funeral was held July 1, with his casket draped in an American flag on account of his service in the Navy. His son Rick eulogized him thus: ``He was my hero and I was fortunate to get a very cool 'Old Man' as my dad. That I got to share him with so many others and they got to see what a great family man he was is something I am grateful to have experienced with him. ''Harrison was survived by wife JoAnne, three sons, 10 grandchildren and five great - grandchildren. Harrison placed his son Rick in charge of his estate. Christopher Keith Harrison, the youngest of Harrison's three sons, was intentionally omitted as a beneficiary in his father's will. Following his death, Pawn Stars ran a commemorative episode,`` A Treasure Remembered'', featuring clips from the show and interviews about him. In the episode, a family photograph is briefly shown; Christopher's face is blurred out.
Document 13: Edward Burd Grubb Jr.: Edward Burd Grubb Jr. (known as E. Burd Grubb) (November 13, 1841 – July 7, 1913) was a Union Army colonel and regimental commander in the American Civil War. He served in three regiments and commanded two of them. In recognition of his service, in 1866, he was nominated and confirmed for appointment to the grade of brevet brigadier general of volunteers, to rank from March 13, 1865. He was later appointed by President Benjamin Harrison as United States Ambassador to Spain. He was also a noted foundryman, business owner and New Jersey politician who was close to Woodrow Wilson.
Document 14: Buchanan's Birthplace State Park: Buchanan's Birthplace State Park is an Pennsylvania state park near Cove Gap, in Peters Township, Franklin County, Pennsylvania in the United States. The park is on Pennsylvania Route 16 along Tuscarora Mountain. Buchanan's Birthplace State Park was created from land donated to the state by Harriet Lane in honor of her uncle, the 15th President of the United States, James Buchanan.
Document 15: William Lawrence House (Bellefontaine, Ohio): The William Lawrence House is a historic house in Bellefontaine, Ohio, United States. Located along Main Street (U.S. Route 68) north of the city's downtown, it is historically significant as the home of William Lawrence, a prominent U.S. Representative during the late nineteenth century.
ground_truth: John Scott Harrison
sub_queries: who was the only u.s. president whose grandfather was also president Answer: Benjamin Harrison
Benjamin Harrison >> father Answer: John Scott Harrison