Yes. My late bloomer finally decides to flip at 4.5 months, after many days of lifting her bum. I did have a nagging suspecion it was a prelude to flips but everyone else says their baby has not/is not lifting their bums so I thought it could be just a quirk of Sophia. Was pleasantly surprised when after a bum lift she threw one leg over to the other side so her bum is flipped over. Unfortunately she hasn’t quite worked out how to turn the shoulders so its still perpendicular to the ground but I’m really proud of my baby as it is.