Is it permissible for my husband to take out loans to build a house for his family and to marry off his brothers, given that there is land that can be sold to pay off the debts and cover the needs of his daughters, and is selling it now at a lower price better than him bearing the burden of these loans alone?

Taking interest-based loans without a شرعي (legally recognized) necessity is considered a major sin, and severe warnings have been issued against it. The husband must repent from it. He is not obliged to pay its interest unless he is compelled to do so. Selling land to get rid of riba (interest) is better. There is no obligation to hasten the repayment of non-interest-based loans before their due date, unless doing so leads to an exemption from interest.

An advice for the husband is to stay away from interest-based loans and from being audacious in matters of religion, and to prioritize the rights of his daughters over the rights of his brothers when rights conflict. He should fear for his weak offspring.