Ait Boulahcen, born in France in 1989, was nicknamed the "cowgirl" because of her love of hats, news.com.au reported .
She is thought to be the cousin of Abdelhamid Abaaoud, the suspected mastermind of the Paris attacks and also believed to be the leader of a terror cell that was about to attack France's Charles de Gaulle airport.
Ait Boulahcen's mother claimed, after her residence was raided, that her daughter was radicalised in recent months.
The 26-year-old's friends and neighbours described her as bubbly and outgoing, but a bit "clueless".