Roll over regression?

Elizabeth • Baby #1👱‍♀️ born August 23, 2018 Baby #2 👶🎀 born May 18, 2020

Has anyone else had this happen? My 15 weeker has been rolling over tummy to back consistently since 8 weeks. For 3 or 4 weeks she was rolling almost immediately upon being placed on her belly. This week it's like she's forgotten how to do it. She'll hold her head up like a champ, but when she's done she now flops down instead of rolling.

She has had a growth spurt recently, so I'm wondering if now she's too chunky? Or could she just no longer be interested while she's working on some other development?

Any thoughts?