With throwing that leech in the fire for Rob Stark it brought up the fact that I always thought it was odd that Rob never teamed up with Stannis. Maybe there's something I'm missing but I thought he was in it for the revenge and the fact that Ned was pushing for Stannis for King seems odd and out of character for Rob to not try and see that through and to lay claim as King of the North it just doesn't seem to jive with the Starks way of thinking.
Robb was in it for revenge and saving the rest of his family but he let his Northmen gas him up for ambition as well. Smart thing to do was to kill the King of the North talk and team up with Stannis. IMO he had two chances to do that too.