He already had to compete with the chickens and now there's another dog??

My cousin brought her yappy little terrier/chihuahua dog and she already hates Chester. My sister M was fawning over her, and he's jealous now, which means he'll be all sulky for the next few weeks. He's such a good dog though. She stole his water bowl and his people, but all he wants to do is make friends with her and she keeps growling and swiping at his nose.

Don't worry, Chester, you're still our favorite chicken.