I have a 25 month old. She needs to sleep 10 hours at night and have a 1.5 hour nap during the day to really feel good, but she often gets only 11 hours total, and sometimes less. Today she slept 8 hours overnight (9 is average) and took a 2.5 hour nap.
I'm in a frustrating period, too. DS (26 mos) refuses to take naps (though he does have quiet time for about an hour in the afternoon where he'll lay down and watch a little TV) and I still have to fight to get him to sleep before 10pm. I have no advice and no idea what to do. He doesn't seem tired or cranky so I guess he's getting what he needs.