She was a member of the Betty Ann Norton Theatre School in Dun
Laoghaire, Co. Dublin for nearly 12 years.
She got 8 A1s in her Leaving Certificate examination in June 2006 at
St. Andrew's College, Booterstown, Co. Dublin and was accepted to study
English at Cambridge University in September 2006.
As of 2021, she is a senior lecturer at the University of Birmingham in England.
Gilligan has written a multitude of novels. She wrote her first novel while she was still in college, and it has reached the number one bestseller's list in Ireland.