Simplify the following text for a Grade 7 native English-speaking person.
Original: Robert Todd Lincoln ( August 1 , 1843 -- July 26 , 1926 ) was an American lawyer and Secretary of War , and the first son of President Abraham Lincoln and Mary Todd Lincoln .
Simplified: Robert Todd Lincoln ( August 1 , 1843 -- July 26 , 1926 ) was an American lawyer and Secretary of War . He was the first son of President Abraham Lincoln and his wife , Mary Todd Lincoln .