DS (just turned two) has until now been a great sleeper. No dramas to be put to pet, always been put down awake, settles himself etc. At the weekend we took the side off his cotbed and he is now a different child. Happily gets into bed but won't stay in it and howls at his door gate for up to an hour (obviously I go in and steer him back to bed calmly but firmly several times). Then if he wakes in the night (which he used to occasionally but managed to settle himself) he's straight out of bed screaming at the gate again. In the early hours of this morning it took me five times of going in there and putting him back to bed. I just can't understand how he has literally changed overnight. Has anyone experienced similar? Is he just testing new boundaries now that there is a different set up in his room? Would love to hear others experiences.