How do I stop adults from teaching my 3 yr old son to be aggressive and playing rough with him?

I have a 3 yr old son. His dad and his older siblings and cousins play rough with him. Wrestling, sword fighting, punching, name calling, etc. They are teaching him behavior that I don't want my son to copy. I don't want him to be aggressive or a bully. How do I get them to understand the damage they can be doing to my son by teaching him this behavior?
Asked Dec 13, 2016

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