This pattern was designed by high school student AC as an assignment for her school’s knitting course. She writes:

So what I wanted to design for my first time was something for my dog. I thought a sweater could really do for him since he has short hair and our Canadian winters are pretty harsh. I wanted something warm and also something stretchy, so it wouldn’t feel too uncomfortable for him. But I didn’t want some plain looking sweater, I at least wanted it to look cute. It didn’t have to be fancy, just cute. :) I hope you like it as much as I do.