Boothby was born in Finchley and, with her older sister Gertrude, lived there with her step-parents Harry and Gertrude Penn. Harry was a civil engineer, and by 1901, they had moved to
South Norwood, where she played at Beulah Hill Club, and during the winter months, she played badminton. In 1908, she won a silver medal in the
women's singles event at the
1908 Summer Olympics. In 1909, when she won the Ladies' Singles at
Wimbledon, the runner-up of the
Men's Singles,
Josiah Ritchie, was also living in Norwood. Also in 1909, she won the singles title of the
British Covered Court Championships, played on wood courts at the
Queen's Club in London, after defeating Madeline O’Neill in the final in straight sets. In 1911, she became the first female player to lose a Wimbledon final without winning a game, losing to
Dorothea Douglass Lambert Chambers 6–0, 6–0. In 1914, she married Arthur C. Geen, a professional architect. She died in
Hammersmith or
Hampstead, London in 1970. ==Grand Slam finals==