Is it permissible for a single mother who loaned money to someone, and he has not repaid it for three years, to recover her money from him if he offers to repay it from ill-gotten gains, provided that he bears responsibility for this money before Allah, and she is absolved of its sin?

Unlawful wealth is divided into two types: The first is that which is inherently unlawful, such as stolen property. This is not permissible for the one who takes it, nor for anyone to whom it is transferred while knowing its status, and it is not permissible to repay a debt with it. The second type is that which is unlawful due to its earning, such as the earnings from singing. This is considered unlawful only for the earner according to some scholars. It is permissible for him to take from it what he needs if he repents and is in need, and it is permissible for him to repay his debt with it. It is also permissible for someone to whom it is transferred through a permissible means to accept it. If the debtor is in straitened circumstances, he must be given respite, and it is not permissible for him to commit a sin to repay the debt.