My DS is 15 months and is brilliant at sleeping at night (7pm-6,6.30am).
he also has a mammoth nap after lunch - usually 1,1,30ish. Here's the thing. He used to wake up naturally after about 2 hours and then we'd get a bit of afternoon together.
But recently he doesn't wake up voluntarily after his nap so I've been waking him at 3.30pm, so that he has a bit of afternoon before supper at 5.30pm. often he is sound asleep and reluctant to wake up and takes a while to rouse.
Today i'm leaving him a bit longer, but i think if i leave him too long he won't sleep at night. don't know. never tried it.
So, do you wake up your LOs to keep them in some kind of routine, or let them nap as long as they want?