I am learning a lot from the replies here. Yes, yelling is never an option. Since, it only makes them more hysterical at times.
When I do take care of my sister's kids and my own, I CLAP really loud to get their attention. And if they're getting rowdy, I do CLAP again and lead them into some kiddie exercises like jumping jacks and marching in place.
Then by some sort of miracle - they LOVE following me right after.. Kind of like a coach/ drill sergeant
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