Here's my story, hopefully it might help someone. i'm still in the midle of it, but so far so good!!
My dd went to one nap about 2 months ago (at 16mo's) and it has been horrible. since then her one nap is generally only 1-1.25hrs long tops! she has been waking sporadically at night and crying alot at bedtime and naps.
i was reading something that Michelle-megsmom sent me and it clearly said that if you're transitioning to one nap and your child ins't getting eough sleep that it will cause early wakings and night wakeups!
it said to put them to bed EARLY! even 6-7pm or earlier!
i had been putting meg downa t 7.... so the other day after a rough night and only a ONE hour nap:(...she was so tired, i put her to bed at 5:30pm!! she went right to sleep, no crying, no wakeups and slept until 6am! you would be surprised how much junk can be related to OVER tiredness. last night i put her to bed at 6pm (you want to aim for 4.5hrs after they wakeup from their nap to be in bed). that's what has worked for us and many others.
anyway, i put her to bed at 6pm and she slept until 6:15am this morning. i heard her babbling at 3am but i didnt' need to go in.
i've also been doign the wake to sleep at the 1hr mark for naps and getting an extra 45min out of her totally 1hr 45min so that's not bad. tonight she will be in bed again at 6:15pm.
you may want to try this!! My sister's 2yr old daughter has also been waking early, fussing at bedtime etc...so last night she put her to bed at 6:50 and she was out cold by 7pm with no fussing. she normally puts her down at 7:30 and she isnt' aslep until 8pm.
so, she was surprised too! sometimes just a difference of 15min to 30min can make the difference of them being overtired or not. you need to do this for 5-7 days as well.
Nicole