It is scary, I know. There was one stage where Sam wasn't very well and he was really unhappy and doing it - then had a massive mucusy spew and was happy and cheery after that, but mostly it seems to be a tired/thirsty thing for him. We gently remove his hand, offer his sippy cup and tell him that fingers don't belong in his mouth. I hope she doesn't make a habit of it!

BW