Give a bride price to the future father-in-law's family. What should I give my brother-in-law if he is here?

Judging from your description, you are going to give your future father-in-law a dowry. Your girlfriend's brother, that is, her brother-in-law, is also at home, so you must prepare a gift for him at this time.

I think you can prepare a lighter or watch. Of course, I think it's best to discuss it with my girlfriend before deciding.