As promised, I have taken a few more videos of Addy running around and well... acting like a DOG. Admittedly, she is a pesky little sister kind of dog, but Wrigley seems to be patient enough. Plus, it certainly won't hurt if he can parlay this exercise into losing a few pounds (but don't tell him I said so!).
Addy loves to chase Wrigley all around the deck and he loves to run from her. You will also notice that Wrigley is too big to fit between the deck slats, but Addy fits just fine. Once she catches up to him she tries to pull on his collar to get him to resume playtime. It doesn't usually work because by the time Wrigley starts to try to escape her for real and not just for the game, he is dead tired.
What a good brother he is.