"A pity because I did send people to check. According to the older servants in Starfall, Ashara Dayne had given birth to a stillborn daughter a few months before Lord Stark even visited. She threw herself into the Torrentine after Eddard Stark arrived with Dawn and the news of her brother's demise. Apparently had no babe with him nor any other retinue. It's quite possible that nobody alive knows who Jon Snow's mother was. It was twenty years ago, and now with King's Landing a cursed ruin and the Riverlands completely devastated, we might never find out."