Re: sukey/sookie/sukie. I just remembered that this term is used fairly commonly downeast in a slightly different sense than the one I mentioned earlier. "Sook" (noun) and "sookie" (adjective) can mean something like the slang "suck" and "suckie" (as in "don't be a suck, suckie baby") but is usually much gentler; more affectionate than contemptuous - a toddler wanting to snuggle with his mother is a "sook"; the same toddler making a fuss because he can't have a lollipop is a "suck". Despite the similarity in sound, I think the terms have separate etymologies; the issue gets confused though because "sook" is sometimes used as a euphemism for "suck" - someone starts out to say "suck" but decides to soften it to "sook". And kids will sometimes apply it sarcastically to one another.

I don't associate "sook" with any particular ethnic group. Someone I was talking to once suggested that it might come from the Mother Goose rhyme Polly Put the Kettle On, the second verse of which has a character named Sukey doing something equally domestic (I forget what exactly). That seems a bit of a stretch to me, though ...