two of my kittens have bald spot on side of mouth please help!

Two of my kittens have a bald patch just on one side of their mouth by their whisker (both kittens have it in same exact spot) it gets slightly scabby and looks a little pink. They aren't scratching or anything. They are still nursing so I don't think it is a food allergy. I figured I would ask here before I took them to the vet. Thanks in advance for your replies!

Do you have a picture? That would be helpful, and it might just missing fur if they were born a bit early. When jay-jay was born, he had almost no hair on his stomach and ears but his fur eventually started to grow. Also it could be fleas or parasites. I hope they get better soon! 

http://www.catster.com/answers/question/why_does_my_kitten_has_a_bald_spot_and_slight_scabbing-52834

https://answers.yahoo.com/question/index?qid=20080315190219AAYxMef

I think I'd get them checked by the vet just in case it's something contagious that might affect the others in the litter.  Let us know what the vet says.