My two kids 5and2 both had play pens for beds until they outgrew them long ways. My youngest 2 is still in hers. She's able to climb in it but not out of it. That's another time I change them to toddler beds. Anyways. I'm on my third baby and I ordered her play pen, I also discovered they now make fitted sheets and mattresses for them. I'm so ecstatic about it. No more wondering if my newborn is cold. No more figuring out when to put a blanket for them in there on the bottom for added cushion. No more worries lol