Rex (?)

Lately, Michael has taken to speaking to Matthew like a dog and calling him Rex.

"Come here, Rex! Come here, boy!" He'll say.

Michael will do this when he wants to herd Matthew from one room to another.

While Toy Story has a Rex, and the boys do like Toy Story, I think the culprit is something entirely different. I think it's a clip from Snoopy Come Home I have occasionally let him watch on YouTube. In it, a little girl takes to calling Snoopy "Rex" and dragging him around violently by the leash and dressing him up:

Good thing it hasn't gone that far, right? I can't even imagine!