It's a toss up between this one and Peter/Edmund brotherly relationship or Susan/Lucy sisterly relationship or Peter/Lucy sibling relationship. Sorry Susan/Edmund sibling relationship, it didn't do it for me.
The 4 reactions when meeting reep in prince caspian "You are a mouse"-Caspian "Oh, he is soo cute!"-Lucy "*horrified look on face*"-Talmarine soldier "*No time to speak* Yes, im a mouse." -Reep to Talmarine