Symbolism of the Stark kids and their Direwolves..
Sansa's direwolf is dead meaning she is no longer a Stark.
Arya's Direwolf is "missing" meaning she is in limbo about being a Stark.
Bran's Direwolf is dead meaning he's not a Stark he's the 3-eyed raven.
Rickon and Rob are dead, so are their Direwolves.
Jon Snow's Direwolf is alive and so is he, he's the only true Stark left.