My baby does too! And alot of time ! Whenever he is crying he does that. It also freaks me out :(
My boyfriend’s nephew who is 19 years old does this - or sounds like it’s the same. He done it a lot as a baby when he was excited, and now he does it when he’s really excited. My sister in law took him to the docs and they said it’s nothing to worry about x
My baby does this too!