Is it obligatory to return a sum of money to the family of a deceased partner after nine years, or is it permissible to donate it to the mosque?

The deceased's money must be returned to his heirs, for the Prophet, peace and blessings be upon him, said: "Whoever leaves behind wealth, it is for his heirs." It is not permissible to donate it as charity except with the permission of the heirs. As for the profits generated from investing the money, scholars have differed on who is entitled to them. Some said they belong to the worker, while others said they belong to the owner of the principal.