When my kids are grumpy, I stick to the basics. A protein-filled snack, bath, or outside time almost always works.
Briefly

"There's just something about water that can calm a kid, even as they get older. It's soothing, something to focus on, it can either cool them off or warm them up..."
"First, we give them food and water. We'll say, 'Let's eat something,' or 'Hey, why don't you take a big drink, and then you can tell me what's wrong.'"
Read at Business Insider
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