She was born in the Dublin suburb of Rathmines, the second youngest of twelve children of Frederick, a Catholic, and Isabella, a Protestant, and a niece of the artist Sir Frederick Burton. The boys were brought up as Catholics, the girls as Protestants. From the age of 16 in 1904 she studied at the Dublin Metropolitan School of Art under William Orpen, where her talent for caricature was discovered. In 1907 she studied fine art at the Slade School of Art in London. Her relationship with Joseph Plunkett is retold in Gerry Hunt's graphic novel Blood Upon the Rose (2009).