DD still in cot at 3 yrs - is this ok?

[FurryFox]

DD was 3 in December and she's still in her cot. Is this still ok? DD1 went into a bed at 18 months as she was a shocking sleeper and it helped for her to be in a bed.

However dd2 loves her cot and is more than happy in there. Has so far made no attempt to climb out, goes to bed at 7pm and wakes up about 7am. Am wondering if we should think about making the transition to bed now? I have visions of her starting school and still being in a cot

If she is happy, so what? You could just take the side off for a bit so she gets used to it, but imo it takes up less room which means more room for playing. My ds1 is still in a cot bed sized bed and he is 4 (but it does look like a bed, not a cot bed). He is happy there and we will get bunks soon-ish, so no point getting him a bed till then.