Bran when he is looking out of you.

You were with Jon and the others in battle and Bran was worried about you so he went into Summer. 

You were fighting an enemy and didn't see someone coming up behind you. Just as you killed your opponent you turned to see someone about to kill you when Summer leapt in front of you and killed them. Summer turned to face you.

"Thanks, Bran." You grinned and went back to fighting. Bran made sure that Summer didn't leave your side until the battle was over.