John was the son of Thomas Cusack and Maud Darcy. The date and place of his birth have not been found.
John Cusack
Thomas Cusack (1490-1571)
Alison Wellesley
sir William Wellesley (<1443-1502)
Ismay Plunkett
Maud Darcy
George Darcy
William Darcy (c1460-1540)
Margaret St. Lawrence (<1513-?)