Is it permissible to eat and stay overnight with a relative who works in the alcohol trade?

If the greater part of a person's earnings are unlawful, then it is not permissible to eat from their food or reside with them. However, if their earnings are mixed, and the lawful portion predominates or is equal to the unlawful, then it is permissible. It should be noted that residing in non-Muslim lands and studying in mixed universities have their own specific rulings.