Is it permissible to take money from the husband and give it to the brother in exchange for him performing household chores, without the husband knowing that the brother is the one who performed them and not external laborers, and for an amount equivalent to the customary wage for such work?

If the husband delegates a task to his wife's brother, the brother is not permitted to hire himself to perform it except with the husband's knowledge. However, if the husband delegates a task to his wife, she is allowed to hire her brother to perform it at market price, without favoritism. There is no blame upon her for doing so, even if it is without her husband's knowledge, and she should pay him the customary wage from her husband's money.