I read a thread a while back where someone said that they had never heard of a DC still in a cot at 2.
Well my DTs are 2.7 and are still in their cots. 
These are very large cots that can be transformed into a bed by taking down one of the sides - I think they are called cot-beds. They are extreamly sturdy so DTs can't shake them about and because DTs are very small for their age, they can't climb out - though I think its just a matter of time.
They sleep very well and they go down at 7pm with no problems at all .... and that is why I am terrified of changing the status quo by taking down one of the sides.
So .... how much longer can I keep them imprisoned?