Genuine question! 3 out of the 5 little ones I look after (not all at the same time) are very into putting everything in their mouths which I know is completely normal, but I am a bit bemused when they put a handful of mud and stones in their mouth, only to have it fished out and yucky noises made at them...only for them to do it again and again...and chew! Surely it must taste disgusting!! I'm all for a bit of mucky play, but at this rate they'll all get worms! What is your tactic on stopping this, or is it just time. They also eat crayons, paint, foam... 