The series follows Pendragon's journey as he discovers he's a descendant of King Arthur and is destined to fight the evil forces of Saint Dane. He learns about his heritage and his family through various means, including historical records, talking animals, and the ancient powers he possesses. However, he never physically meets any direct blood relatives in the series.
It's worth noting that there is a character named "Pendragon" in the *Merlin* series by T.H. White, but he is not related to the character in the *Pendragon* series.