1. Treat her with respect.
One way to win over the overprotective brother is to treat his sister with as much respect as he does. He won’t have any logical reason to dislike you if you show his sister the love that she deserves.
2. Don’t avoid him.
He might scare you at first, but don’t let his big brother act get to you. The worst thing you can do is avoid seeing him. Not only will he be well aware you’re blatantly trying to not hangout with him, but his sister will be too, and her brother is someone who is in her life not by choice, but by genetics. No matter how annoying, awkward, or tense the situation might be, just get over it, and remember if you want to be with her you have to put up with her brother occasionally too.
3. Learn his interests.
This goes a step further than simply not avoiding him. If you get a sense of what his likes and interests are you’ll be able to ease the tension and awkwardness when you do see him. Small talk over golf may not be your forte, but if you make an effort he’ll notice, and while he might not appreciate it, your girlfriend will.
4. Pick your battles.
You and her brother will most certainly not agree on everything, especially when it comes to your girlfriend. Pick your battles. Don’t argue over everything. Arguing with him increases the tension between both your relationship, and the relationship you have with his sister. Your girlfriend doesn’t enjoy the fact that you can’t get along with her brother.
5. Understand that he wants the best for his sister.
He’s protective of his sister because he wants the best for her. Understand that his actions reflect this and accept it. You can’t change him, and you shouldn’t try.
6. Let him know that you want the best for his sister too.
While you may find him to be completely irrational, you both have one thing in common. You love the same girl, but in very different ways. You want the best for his sister and so does he. Remember that.
7. Don’t PDA in front of him. (Ever)
Her overprotective brother can barely stand to see you have your arm around her, and while it’s completely appropriate to hold your girlfriend’s hand and kiss her cheek whenever you choose, her brother might disagree. Just be aware that he’s constantly watching you when you’re around. A butt grab might be a bad idea.
8. Be willing to apologize
Sometimes her brother’s overprotective ways will make you angry, and sometimes you won’t be able to handle him in a cordial manner. It’s okay if you mess up in dealing with his overbearing personality, just be able to apologize when you know you’ve done wrong.
9. Don’t expect many apologies on his end.
Be the bigger person. While you may be willing to apologize for your wrong-doings, her brother might not be so agreeable. He’s not going to apologize about the love he has for his sister often, if ever.
10. Know that he will always be in her life.
Her brother is family, and he is there to stay. You are her boyfriend, and you know what they say about boyfriends, they come and go. If you want to stay in her life you have to understand that her brother will always be a part of it, all of his overprotective quirks included. If she means that much to you, you will make it work.