So one night, when Karsten was about 9 days old, my mom and I were sitting in the living room and Karsten was on the floor getting in a few minutes of said tummy time. She was not a fan, and the next thing we knew, she rolled herself over from her tummy to her back. I thought it was a fluke. 9 day old infants are not supposed to be rolling. That comes later. I even Googled it. Average time to start rolling from tummy to back is about 4 months.
Fast forward to 13 days old, and I had her back on the floor for some more tummy time. She rolled over again. And again. And again.... I started to get the point. She absolutely hates tummy time.