When Letterman asked if there's a rivalry between Exton and Avri, Downey told him, "Not yet. It's natural for Exton to want to bite her once in a while. It can start off as a little pet and then it turns into a nibble. I think it's just establishing dominance. She'll be running stuff at some point."
With those beautiful blue eyes, we have no doubt Avri will be getting her way!