Her mothers fifth marriage to Boson of Mastas, Seigneur de Cognac, produced a half-sister named Martha, Viscountess of Marsan, who married Gaston VII, Viscount of Béarn.
By the time of Petronilla's fifth marriage and the birth of her daughter Martha, she required a stronger union so arranged for Alice to marry Jordan, Lord of Chabanais,[4] a relative of Boson of Mastas.
De Montfort had interpreted this act as a gift, so refused to hand Bigorre over to Alice on the death of her mother.
To prevent Guyenne and Gascony from rebelling, Henry III of England recalled Simon de Montfort and appointed John Grailly in his place.
Upon Eskivat's death, control of Bigorre was disputed between Alice's sister Martha and her daughter Laura, with the latter eventually succeeding.