I'm making a model of a cartoonish cat that i drew up. I have it started with a head, neck, and body that are all seperate. Well I want to combine them together and im trying to merge the edges of the seperate parts(ie head to neck, neck to body) but once i select an edge on the neck, it won't let me select an edge of the body to connect it. Just wondering if there is something special I need to do or what? Any help would be greatly appreciated

rob