Adorable dog dressed as the Phillie Phanatic makes Phillie Phanatic do adorable things

We're not quite sure just what the Phillie Phanatic is. Is he a kind of cryptozoological marvel? Proof of alien life that Mulder was trying to convince us were real? Is he even carbon-based?
On Friday, we perhaps got ever-so-closer to the answer: He appears to be some kind of animal. How else can you explain how well he's able to get along with this dog-dressed-as-a-Phanatic during the Phillies' Bark at the Park night?

Wait -- which one is the real Phanatic?!? Quick, someone ask them something that only the Phanatic would know, like "What's the best way to upset Tommy Lasorda?"