He's got this from a friend who doesn't like her toys being played with by other children and now he's using it for every situation he doesn't like. ie.
Mummy is chatting, he shouts stop it at the person I am talking to. He doesn't want to eat his dinner, he shouts stop it at the plate. A child he doesn't know sits near him and he tells them to stop it. Ladies talking too loudly in cafe, he shouts stop it When people laugh and he is not in on the joke
So far I have said, "thats not kind, we don't tell people to stop it" type things but it continues. It's annoying more than anything because it makes him sound like a grouch when really he is not! Is this a phase? When will he stop it!
But if we dont "stop it" (whatever the thing is that's wound him up this time) he will cry and wail and cling to me. My DM has laughed but she's the only one. I normally say "But they are only laughing/eating/talking/breathing, and that's good!" through a plastered on smile!
Oh the joys of being two! I m on my third two year old and I still die with embarrassment at some of the things she does when out in public. Try and ignore, smile at strangers, don't go out for the next year! Seriously when 'stop it!' Stops then something else, equally unpalatable will start. It's a phase that one day you will look back at and laugh!?!?!?!