If your wife doesn't have the common sense to put him in his place herself, I wouldn't be worried so much about your brother as I was about her.

I would nicely ask him to stop and if not then i would cut ties with him because he should have enough respect for me not to do that especially so blatantly. If my wife on the other hand was reciprocating on his advances i would consider talking to her about whether we were really right for one another. If i had a wife that is lol.

My brother in law started pullin moves on me (eeeew...I asked him to leave me alone with that stuff but unfortunately he's stupid) so I let my husband know and he had a talk with his brother and I haven't had any problems since except that my brother in law doesnt like me very much anymore...but that's fine with me.

I'd wonder what was wrong with my wife to just keep accepting the moves.
I would have a private discussion with both of them first, individually, then go from there.

I wouldn't blame only the wife! I would certainly talk to her and ask her how it makes her feel.She may just be afraid to go off on the brother in fear of being the cause of a ruined relationship between yall. You should let her know that it's not ok and you should give her the ok to tell him to hit the road. If she doesn't then there's a problem. It would be best if she is the one who tells him to stop though. I still think you should have a little chat with the both of them seperately just to make sure everyone understands. If he keeps on, I'd definitely distance myself from him.

I have a twin sister and she used to do things to get attention from my partner and it is very hurtful. I also have an older sister who certainly doesn't care to go out of her way to try and get attention from my partner. It's so wrong and I would never, no matter what allow anything like that to go on between myself and my sister's men. I believe in keeping to yourself. There is no reason for hitting on or allowing people to hit on you when you're with someone. A line must be drawn.