My sisters daughter (7) keeps hitting my daughter (5)?

My sister does nothing about it but put her daughter in the corner. My daughter may be younger but she’s bigger than her cousin, am I wrong to teach my daughter to defend herself?
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+1 y
Not to mention, they’re living under my roof and any time I correct my niece, my sister gets upset with me… so I essentially told me daughter that if anyone hits her, she has my permission to hit them tf back.. how’s my niece gonna learn to keep her hands to her fuckin self?
My sisters daughter (7) keeps hitting my daughter (5)?
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