Should I stick up for her

My girl hates that i dont stick up for her, when my brother insults her, its so hard and confusing, should i stick up for her even if hes only joking. Please i need advice.

families can be hard work. but if your brother clearly makes fun of her- you ought to jump in regardless of who said what. it may be petty teasing but just put your arm around her casually and tell ur brother to lay off. if its a bit more serious than that, have a friendly word with your bro and just ask him politely to ease off x