My little girl was doing this sooo bad at around the same age! She’s not as bad now, still bites her fingers though 🤣. I don’t think it’s anything you can stop. My little girls just turned 6 months & still shoves her whole fist in sometimes 🫠🤣 x
It’s normal for babies they use their mouths to discover things
Don’t think you can. It’s all part of them exploring their bodies. Hopefully they figure out not to do it to make themselves sick though