[2] On April 28, 1859, Booth married John Sleeper Clarke at St. Paul's Episcopal Church, in Baltimore, Maryland.

Because the assassination of Abraham Lincoln in 1865 was committed by her brother, John Wilkes Booth, she and her husband emigrated to England, where they stayed until the end of their lives.

The Unlocked Book: John Wilkes Booth, a Sister's Memoir was written in 1874, but she kept its existence secret, fearing it would upset her husband.

[clarification needed][1]: 23–24 The memoir was published in 1938 by G. P. Putnam's Sons, when her heirs felt the public would be receptive.

[1]: 25–26  Her other family memoirs, which she was able to publish during her lifetime, focused on the acting careers of her father and her brother Edwin Booth.