I'm guessing the answer to this is yes.

My son only very rarely sleeps 12 hours overnight. Last night he slept 7-6 (well, really the "new" 5 a.m.) with one wake to eat. Even when he sleeps straight though he only sleeps 10 hours. I try to feed him and get him down again but he doesn't have it, unless I put him in the swing. Oh, and he doesn't make up for it during the day - he's not a good napper. He's 5.5 months. Perfectly happy baby and not fussy.

Anyone else have a baby that doesn't sleep 12 hours overnight? Oh, and if your kid now sleeps 12 hours overnight, have they always done that?