We who get periods all experience them in different ways. For me, I get a bit more irritated and I eat a lot more and also become either a lot more happy or a lot more depressed during PMS.

My sister (13), she gets more irritated and rude, sarcastic, grumpy, and mean. She blames everything she does on her period and insults others and treats them rudely, and then sulks when she gets told not to be that way.

How can I help my sister on her period while also helping others and helping her be less rude?