I travelled with my King Charles Cavalier who weighed 22 pounds for 15 years. We would fly from Canada to Key West about 4 times a year. He had a large Sherpa bag and was very comfortable in it. In the smaller aircraft the top of the bag would go down a bit but he didn't mind it at all. He has sinced passed away and now Bella has a medium sized Sherpa and it is great. She weighs 6 pounds and a small would have fit her but having to be in there for such a long time I wanted her to be comfortable. I would get the large Sherpa and I am sure you will have no problems |