My 7 m.o. DS is rolling and sitting (although he still falls over relatively frequently). He spends a lot of time happily playing on our kitchen floor while I MN do housework. It's a hard stone floor so I have one of these foam mats down to stop him bashing his head.
Looking at it in the shop it says from age 3+ and I can see why - DS is always pulling up the tiles to chew them and it's becoming a bit of a hazard.
What can I use as an alternative, or should I just be less pfb and let him roll around on the tiles?