Booth was born in Bel Air, Maryland, into the English American theatrical Booth family. He was the illegitimate son of the famous actor, Junius Brutus Booth, an Englishman, who named Edwin after Edwin Forrest and Thomas Flynn, two of Junius' colleagues. He was the elder brother of John Wilkes Booth, himself a successful actor who gained notoriety as the assassin of President Lincoln. Nora Titone, in her book My Thoughts
Robert Lincoln rescue
Edwin Booth saved Abraham Lincoln's son, Robert, from serious injury or even death. The incident occurred 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. 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.  Booth did not know the identity of the man whose life he had saved until some months later, when he received a letter from a friend, Colonel Adam Badeau, who was an officer on the staff of General Ulysses S. Grant. Badeau had heard the story from Robert Lincoln, who had since joined the Union Army and was also serving on Grant's staff. In the letter, Badeau gave his compliments to Booth for the heroic deed. The fact that he had saved the life of Abraham Lincoln's son was said to have been of some comfort to Edwin Booth following his brother's assassination of the president.

Q: who did he save
A: Abraham Lincoln's son, Robert, from serious injury or even death.

Q: where did this happen
A: The incident occurred on a train platform in Jersey City, New Jersey.
What caused this
The incident occurred while a group of passengers were late at night purchasing their sleeping car places
The incident occurred while a group of passengers were late at night purchasing their sleeping car places