If you guys arent on the same page anything you do is pointless. I would have a sit down with you/your spouse/child and keep it short and simple (it’s not nice, how would you like to be treated that way, consequences if need be). You need to dig deeper and see if it’s truly bullying or just being mean on random occasions. It sounds weird but there is a difference, especially at that age. Bullying is not kids being kids, it’s about control and can start at any age.
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