I don’t recall this character.
According to the IC wiki:
Nolfavrell Quimbysson was the son of Birgit and Quimby (who was murdered by the Ra'zac when they invaded Carvahall). In the Battle of Carvahall, Nolfavrell proved to Roran that he was a capable warrior by killing one of the Imperial Soldiers with a dagger.
He escaped along with the rest of Carvahall to Surda, with his family.
Unlike Birgit, Nolfavrell seemed to have no quarrel with Roran regarding the death of Quimby. It is unknown if he was even aware of Birgit's potentially murderous intentions towards Roran.