How does a Muslim Al-Albani advise his elderly female relative who deals in usury and lives off its profits, and who does not understand the unlawfulness of such money due to her lack of knowledge, and how should he deal with her if she insists on her action?

A man should gently and kindly advise his wife about the impermissibility of dealing with interest-based banks and the danger of consuming usury. If she insists, he should consider what is most beneficial: if shunning her would deter her from this evil, then he should shun her while informing her of the reason. If continuous advice is better, then he should persist in that.

If all of the wife's income is unlawful, it is not permissible for him to eat from her money or benefit from it. However, if her money is mixed between lawful and unlawful, it is permissible to benefit from it, though it is disliked.