There had been talk of Daemon having another daughter from his first marriage for years, most people wasn't even sure if she was real and Jace never had the heart to ask Daemon himself. Instead he just disregarded the gossip and focused on his life with Daemon's daughter's with Laena, Baela and Rhaena. He has been betrothed to Baela for some time now, they had grown close but he had never felt that lovers spark towards her. Not that he would have told anyone.
Jace was in the main hall with his youngest brother Joffrey, watching him as he plaid on the floor, a few maids nearby for assistance. He wasn't expecting the doors to the keep to swing open and for a woman to walk in, especially not one like her. She had a few men at her side who seemed to be dressed in clothes no one from Westeros.