We say a mattress on the floor is the best first transition. Once your child is staying on their mattress on the floor (ie. not rolling or falling off) then you can put the mattress into a bed frame. If they do climb out of their bed and are very tired it may be hard for them to climb back in. We have heard endless stories of parents finding their child sleeping on the floor or standing against their new bed because they couldn’t get back into the bed during the night. We believe a mattress on the floor is best to start.
Often saying goodbye to their crib can be challenging for children even if well timed. We recommend being open and empathetic. You could say, “You loved your crib and this new bed is big. You don’t like it. I understand. It is difficult when things change. You are growing and I think this bed will be easier for you to use all by yourself. Can you climb into this new bed all by yourself? What should we put near your new bed to make it comfortable?” It may take a few weeks for your child to settle into their bed. During this time they may need a little more help from you to get to sleep at night and for naps. If you offer the least possible help each night soon they will be sleeping well without the crib.