I have lots of little bits of headcanon from him from all the little fic I’ve been writing. Let’s see…well, first off, I think that, physically, he’s bigger than his brother - more muscle, slightly larger bone structure. When he gets injured, if it’s in the middle of a fight, he’s unlikely to stop fighting until he physically can’t move any more or the enemy has been defeated. Um…oh, and that when the twins and Aela were young, they all used to run around and create havoc in Whiterun on the occasions where Aela’s father would bring her into town.