DS is 2y4m. Until about June (so just before he turned two) he was a brilliant sleeper, had a two hour nap daily and then slept from 8-7. He then dropped the nap and it's never felt quite like we adjusted to a new routine, but in the last few weeks (maybe about the last six weeks?) it's gone to hell!
He started waking in the night when he dropped his nap (we tried very hard to keep him having it, but nothing doing). Recently he would wake up multiple times saying his nappy needed changing, so we took that as a sign to start potty training, which has gone very well but the night wakings have got much worse since then (he finds various reasons to call us in, but needing a wee or having a wet nappy are the most frequent). We're now in this cycle where he's totally exhausted all the time, but if he sleeps during the day (which he will only do in the car, and can't be transferred from the car anymore so it's not a great solution!) he wakes even more in the night and is worse the next day. If he doesn't then, like today, he's inconsolable with over-tiredness by 4/5pm, which also means he won't really eat dinner. It feels like we've got stuck and just need to find something and stick to it, but I'm not sure what - neither trying to push through without the nap or taking him out to get him to sleep seem to be the solution, but maybe we're not sticking with one or the other for long enough?
The broken nights aren't great but my bigger concern is the effect on him in the day - nursery have also commented that by the end of the day his behaviour is really different because he's just so tired. He's otherwise a really happy, good natured little boy so it's horrible to see this effect on him.