how to stop DD (toddler) from pinching?

jgb2000

DD's teacher told us that for 3 weeks she's been pinching and roughly grabbing wrists (to the point where she leaves finger marks)! We've talked to her and I reminded her today at drop-off that we don't pinch and we don't grab. It's happening more with one little girl who I know she likes. The teacher said they're frenemies right now. My DD sits across from the table from her and makes the pinching motion into the air! What a little bully!

She grabs her little brother (he's 1) and we stop that but she hasn't really pinched at home.

Any tips would be appreciated. I don't want her to become 'that' kid...