When her father died in 1597 she was sent to live with her grandmother, Mabel Browne, Countess of Kildare, in Maynooth.
Her son, Hugh Albert O'Donnell, was born in 1606 in Maynooth and became known as the 2nd Earl of Tyrconnell, having inherited the title upon his father's death in 1608, and long before the attainder of 1614.
[6] Due to increasing hostility from the English nobility,[7][5] Rory fled Ireland in September 1607 whilst Bridget was pregnant with their second child.
[3][8] It was apparently a "snap decision",[9] and as Bridget was staying at her paternal grandmother's Maynooth estate at the time, far away from the point of departure in Rathmullan, she was left behind.
[14] MacGrath attempted to persuade Bridget to leave Ireland a few weeks after the flight, though she refused.
[10] She wrote in Irish, but only one of her poems has survived, a work in an elegant classical style from about 1607.