This quest begins immediately after you have fled Athens. You should sail east to the island of Naxos where it is hoped that your mother, Myrrine, can be found. As you approach Naxos you will find a place to dock your ship at the port in the north west of the island. Once you have successfully docked, make your way to the Temple of Dionysos in Naxos. There you can enter through the main door and be reunited with your mother. After some brief scenes of dialogue with your mother, a soldier will appear warning of an incoming attack. Follow your mother to the nearby horses and on to meet the attackers.
When you reach the Temple of Demeter, dimount your horse and join the battle in the bay below. The attackers are not difficult to defeat and you will have help, but try to focus on those which are fighting with your mother. When all of the invaders are dead, the quest will complete and you can speak with your mother.