This article is about the person. You may be looking for Cadoc (horse).
Cadoc was the father of Garrow and Selena and the maternal grandfather of Murtagh and Eragon, as well as the paternal grandfather of Roran. He was the paternal great-grandfather of Ismira (daughter of Roran and Katrina). He is deceased long before the events of the Inheritance Cycle and so never appeared in the series, but was mentioned infrequently. His grandson Eragon would later name his horse after Cadoc.