What is the ruling on a husband spending on his brother when his own household is in need, knowing that his brother works, his wife works, and he earns less than the husband?

If the items needed for the marital home are those without which life would usually be difficult (such as beds, refrigerators, and cooking appliances), then they are included in the husband's obligatory maintenance (nafaqa).

It is not permissible for the husband to prioritize his brother over his household in terms of maintenance, except after fulfilling the obligatory maintenance for his household. This is because maintenance for the wife is a matter of exchange (mu'awadah), while maintenance for a relative is a matter of solidarity (muwasah), and exchange takes precedence over solidarity.

If the husband has fulfilled the obligatory maintenance for his wife, then it is permissible for him to provide maintenance for his brother and other relatives. If the brother is entitled to maintenance from his brother, then the husband must spend on him to the extent of sufficiency.

If the husband is not obligated to maintain his brother and the brother is in need, it is better to give charity to him due to kinship. If the brother is not in need, then giving charity to the poor is preferable to increasing expenditure on oneself, one's family, and relatives beyond the level of sufficiency.