What a cheeky monkey! Do you have a mattress you could put on the floor next to the cot JIC she falls out overnight rather than changing over to the toddler bed? Otherwise, the only advice I can give you that worked wonderfully for DS1 (who was 23 months) and DS2 when they went into a bed was to tell them they aren't to get out of bed unless mummy or daddy comes to get them! They could call out to say they are awake, but they were not to get out of the bed until we arrived. Even at a young age, toddlers understand a lot more than we give them credit for . Both boys to this day stay in bed until we come into their room or call out to them, even though we've told them they can now LOL!

Good luck tonight!!