Druid in Flight — Jean Hart Stewart

Book 8 in the Garland of Druids series but may be read as a standalone novel. When Triona flees the home of Fergus, her lecherous brother-in-law, she takes her young brother Conor and dashes for Wales. She knows Fergus will soon be after them. Conor helped her escape by wielding a poker, leaving Fergus senseless and with a broken arm. They head for the home of Sianna, a Druid cousin, and wife of Dr. James Randall. The Randalls' weekend guest Aiden Thomas at first refuses to welcome strangers. When one transforms into a beautiful young lady, he soon fights to conquer his overwhelming attraction for her. He has no room for anyone else in his life. Aiden must deal not only with desire, but also with his greedy and cruel father. And he must protect his mother and Triona. Then when Fergus appears to wreak vengeance on Triona and Conor, everyone is endangered.