I would be okay with both.
For the mommy, she'd have to baby me hardcore, and want me to be as babyish as possible. Though if I got fussy or tried to be a big kid, i'd be okay with some stern punishments, involving bondage, suppos, and a very full and messy diaper.
For a babysitter, it'd be kind of the opposite, but still kinda the same. Instead of loving, she just does her job, force feeding me all the food for the night in a sitting, stuffing me with mushy baby food and lots of milk, then locking me in somewhere nearby in a bondage situation, possibly with either something up my bum to force me to clean out dinner, or a special meal afterwards (high fiber, pruney, or fast acting lax like caster oil) that ensures my diaper gets filled, and then puts a paci in my mouth and just does whatever she wants, while I lay there helpless to stop anything filling my diaper, and I'm left to stew in it until her job is done for the night.
Either way, bondage, suppos, and forced to use my diapers, personally I'd like the loving yet stern mommy, cause being treated like a helpless baby is what I do it for