Lincoln had a distant relationship with his father, in part because Abraham Lincoln spent months on the judicial circuit during his formative years. Robert would later say his most vivid image of his father was of him packing his saddlebags to prepare for his travels through Illinois. Abraham Lincoln was proud of Robert and thought him bright, but also saw him as something of a competitor and once said "he guessed Bob would not do better than he had. The two lacked the strong bond Lincoln had with his sons Willie and Tad, but Robert admired his father and wept openly at his deathbed.
Following his father's assassination, in April 1865, Robert Lincoln moved with his mother and his brother Tad to Chicago, where Robert completed his law studies at the University of Chicago (a school different from the university presently known by that name). He was admitted to the bar on February 25, 1867.
On September 24 1868, Robert Lincoln married the former Mary Eunice Harlan (September 25 1846 - March 31 1937), the daughter of Senator James Harlan and Ann Eliza Peck of Mount Pleasant, Iowa. They had two daughters and one son:
The last descendant of Abraham Lincoln, Robert Todd Lincoln Beckwith, died in 1985.
His mother's "spend-thrift" ways and eccentric behavior concerned Robert Lincoln. To gain control of his mother's finances, he had her committed to a psychiatric hospital in Batavia, Illinois in 1875. She was released after a three-month stay. The committal proceedings led to a profound estrangement between Lincoln and his mother and they never reconciled.
Following his service as Secretary of War, Lincoln helped Oscar Dudley in establishing the Illinois Industrial Training School for Boys in Norwood Park in 1887 after Dudley discovered "more neglected and abandoned children on the streets than stray animals." The school relocated to Glenwood, Illinois in 1899, beginning to enroll girls in 1998. Under the name Glenwood School for Boys & Girls, the school continues to operate as a haven for boys and girls whose parents are unable to care for them.
A serious amateur astronomer, Lincoln constructed an observatory at his home in Manchester, Vermont, and equipped it with a refracting telescope with a six-inch objective lens. Lincoln's telescope still exists; it has been restored and is used by a local astronomy club.
In an odd coincidence, Robert Lincoln was once saved by Edwin T. Booth, brother of John Wilkes Booth, from possible serious injury or death. The incident took place on a train platform in Jersey City, New Jersey. The exact date of the incident is uncertain, but it is believed to have taken place in late 1864 or early 1865, shortly before John Wilkes Booth's assassination of President Lincoln.
Robert Lincoln recalled the incident in a 1909 letter to Richard Watson Gilder, editor of The Century Magazine.
"The incident occurred while a group of passengers were late at night purchasing their sleeping car places from the conductor who stood on the station platform at the entrance of the car. The platform was about the height of the car floor, and there was of course a narrow space between the platform and the car body. There was some crowding, and I happened to be pressed by it against the car body while waiting my turn. In this situation the train began to move, and by the motion I was twisted off my feet, and had dropped somewhat, with feet downward, into the open space, and was personally helpless, when my coat collar was vigorously seized and I was quickly pulled up and out to a secure footing on the platform. Upon turning to thank my rescuer I saw it was Edwin Booth, whose face was of course well known to me, and I expressed my gratitude to him, and in doing so, called him by name."
Months later, while serving as an officer on the staff of General Ulysses S. Grant, Robert Lincoln recalled the incident to his fellow officer, Colonel Adam Bardeau, who happened to be a friend of Edwin Booth. Bardeau sent a letter to Booth, complimenting the actor for his heroism. Before receiving the letter, Booth had been unaware that the man whose life he had saved on the train platform had been the President's son. The incident was said to have been of some comfort to Edwin Booth following his brother's assassination of the President.
He was later interred in Arlington National Cemetery in a sarcophagus designed by the sculptor James Earle Fraser. He is buried with his wife Mary and their son Jack, who died of blood poisoning at the age of 16 in London, England.
Lincoln was the last surviving member of both the Garfield and Arthur Cabinets.
Of Robert's children, Jessie Harlan Lincoln Beckwith (1875 - 1948) had two children, Mary Lincoln Beckwith ["Peggy" 1898 - 1975] and Robert ("Bud") Todd Lincoln Beckwith (1904 - 1985), neither of whom had children of their own. Robert's other daughter, Mary Todd Lincoln ("Mamie") (1869 - 1938) married Charles Bradley Isham in 1891. They had one son, Lincoln Isham (1892 - 1971). Lincoln Isham married Leahalma Correa in 1919, but died without children.
The last person known to be of direct Lincoln lineage, Robert's grandson "Bud" Beckwith, died in 1985.