We recently moved our 2 year old (3 next month) into a single bed from a cot. We'd tried taking the sides off the cot before at around age 2 and he'd just come into our bedroom mulitple times a night so we put him back in the cot. He's generally a pretty good sleeper and before this move was sleeping 11-12 hours and occasionally woke up once and shouted for us but was easy to resettle. He often wasn't properly awake on those wake ups and simply needed a stroke on the head and a bit of ssh-ing to get back off.
A week or so ago we moved him into a single bed. Really keen on it and doesn't want to go in the cot anymore. But other than the first night where he slept well, he's now waking up/crying out up to 4 or 5 times a night and waking us up and also getting up at or before 6am for the day (previously woke up between 6.30 and 7.30). He's not been regularly napping for a while now so that hasn't changed and he gets plenty of fresh air and activity during the day so should be tired. The only fairly recent change, though this was before the move to a bed, is that he's now potty trained during the day. Still in nappies at night which are sometimes dry but sometimes still wet. He does have a cold at the moment but never usually wakes up so much with a cold and he's not waking himself up through coughing or anything like that. For the first few days getting him down was really hard and taking up to a couple of hours but now that is generally much easier though we do have to lie with him til he drifts off. He's slept in beds at other people's houses/on holiday for a while with maybe one wake up a night.
We also have a 4 month old so this is pretty exhausting. I'm getting a gro clock today to try. Any other suggestions or anyone been through this? I'd put him back in the cot but he really doesn't want to!