I meant to post this on March 1st, but this will have to do.
When Edward III came to the throne, the barons who had rebelled against his father were forgiven, and their titles and lands returned to them. Unfortunately, the charter which originally conveyed the Lordship of Gower to John de Mowbray and Alina, was not valid. In typical form, William de Breos was negligent in obtaining the licence of the king, so Alina did not qualify.
But although the act of parliament did not operate in favour of Alina, the magnanimity of the king was graciously extended to her. Gower was returned to her, and the gift was legalised by charter, dated 1st March 1327.
Alina returned to live out her days in Oystermouth Castle, where she built a chapel. Local legend has it that her ghost has been seen in the castle, and she is known as the White Lady of Oystermouth.