I know I already added this and your other Game of Thrones fanart (including the Clegane hounds), but having started watching the show and having finished Book 1 and started reading Book 2, I thought of giving my thoughts on this. XD
I really like the designs you gave them if they were wolves, with cute lil' Rickon pulling Bran along after his brothers and sisters.
My favorite character is definitely Jon Snow, because I just adore those types of characters who struggles with themselves and I love his Night's Watch story-arc. I like all of the story-arcs in the series. I really like that you made Jon darker than his brothers and sisters, with light markings here and there on his paws, and how he looks very different than the rest of them. It really shows his bastard status. And I love his relationship with Arya and Samwell Tarly.
I also really love your designs of the Clegane brothers, Sandor and Gregor, and that they're mastiffs. It suits them very well, since mastiffs are strong powerful dogs.
Keep up the great work!