Hi Dottymo,
My avatar, Tinkerbelle is always cold.....she is a Chihuahua. I made a Simplicity #3939 pattern for her. I used view A which has 4 little legs outof fleece..for the ribbing at the edges...I recycled some from a sweatshirt that I cut off the long sleeves. She loves it.
There are other views with short sleeves on this pattern...VERY easy to sew. Calls for 1/2 to 3/4 yards of fabric.