There is something to be said about being able to use the theme song for the Beverley Hillbillies in a scholarly presentation. Well done SuKi! :-)
It is definitely only used in southern U.S., probably only mountain dialects. It is one of the words that cemented the characters in that show as "Hillbillies".
Wow, suki is here.
Kin is Southern (Appalachian most likely). It´s only used in the legal world now as it next-of-kin as people have mentioned in criminal cases, and in probate law. So, unless you are in the legal field, forget it.