mrs kirky,
i have no idea how they may have affected your LO, but my mum made no secret of adding a little nip of brandy to some warm milk to help me sleep as a toddler. and there's an absolutely horrendous story about another family member who followed the same tradition with his LO mistaking the methylated spirits for brandy, and everyone ending up in the ER at 2am. NOT from my particular gene pool, i hasten to add.
i tell you this not to advocate the use of alcohol on LOs, but just to let you know that it -- intentionally! -- was given to me, and i think i turned out ok. and the meth spirits story, well, far worse accidents do happen than getting into the christmas choccies, and my cousin is a healthy strapping, 6ft 6 scot.
i would keep a close eye on your DS, and if you're at all worried, call the doctors. that's what they're there for!
good luck
katy
p.s. forgive me for joking, but maybe your LO was just a teeny bit hungover with the grumps