Her mother, Jane de Vere, was Irish, and traced her descent to the 15th Earl of Oxford; she would inherit Issercleran, Craughwell, County Galway in 1914.
De Burgo, or Burke, was a native of Craughwell, County Galway, listed by Hugh Fenning as Of the family of Cahirkinvonivy. He was professed at Athenry in 1648 and studied for six years in Segovia, later living in Pesaro, Treviso and Milan.