Is it permissible for a woman to pay financial assistance to her sister's son from her private money with the intention of recovering this amount later from the usurious interest deposited in a bank in her country, given her current inability to access these interests?

It is permissible to deposit money in usurious banks for safekeeping out of necessity, and one must limit it to a current account. If the deposit results in usurious interest, then one must dispose of it by spending it on the welfare of Muslims or for the poor and the needy. It is permissible to give some of it to needy relatives. If the sister's son is poor and needy, it is permissible to give him from the unlawful money according to his need. It is not required that it be from the exact deposited money; rather, it is permissible to give an amount equivalent to the unlawful interest from one's own money with the intention that it is from the unlawful interest.