My 6 month old has started flipping onto her tummy from her back constantly. She won't lie flat on her mat anymore and just immediately rolls to tummy but she can't roll back again so is getting very frustrated. It's really hard to know what to do with her and I can't get anything done at all because she needs me to constantly roll her back only for her to roll and her frustrated again! I'm going to get her a jumperoo but any other ideas for what I could do with her to help her learn to roll back or just to keep her content? Thanks