Prohibition of eating what is unlawful

Q: My brother-in-law is working as a lorry driver in an alcohol company. He distributes wine. Can I visit my sister and eat at her house? Can I take money from him as a debt or the like? Moreover, he built a building from the money earned from this work.

A: Visiting your sister is permissible as it is a kind of keeping good relations with your relatives. As for eating from the house of your sister, you are permitted to eat from the house of your sister if her husband has another legal means of gaining. Otherwise, you will not be permitted to eat at their house because the money he earns is unlawful. May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.