Egelina de Courtenay

She was not a daughter of Sir Hugh Courtenay, MP and Philippa Courtenay primary sources confirm they only had two daughters, Joan and Eleanor.

The peerage of Ireland: Volume 1, page 128, mentions Ulick (the red) De Burgh, of Clanricarde married Egelina, daughter of Hugh de Courtenay. A source for this statement is not provided and no details are recorded to identify Hugh de Courtenay.