Morgad is the son of Murtagh and a young woman from Palancar valley. They fell in love when the woman, who is named Irla, was out wandering in the Spine, collecting berries. Murtagh was there trying to find the place where Eragon found Saphira's egg, for it intrigued him. They fell in love instantly and Murtagh brought Irla back to his castle. They had a child, Morgad.
Morgad is the rider of Raudhr. Raudhr means Red in the Ancient Language, and that is te best way to describe Raudhr. Raudhr looks very much like thorn.
Morgad fights with a sword named Haina, or harm. It is brilliant red with a ruby in the pommel. Morgad is kind of young yet, so there isn't much energy in the ruby.