First of all, this is your own sister's wedding, and as his own brother, you not only don't need to pay any gift money, but also give you a lot of money as your brother-in-law. It is also a big red envelope here.

Whether in the south or the north, in fact, our customs and habits are the same, that is to say, when a woman gets married, her brother must help her sister wrap a blanket in red cloth. When this blanket is sent to the other party, the other party needs to give you a red envelope, which is very lucky and doesn't need to cut you any money.

But as a brother, you must always stay with your sister. You can't leave until he gets married. This is also one of our customs.