Is it permissible to demand repayment of a loan after forgiving the deceased debtor, if his heirs become wealthy?

We bring good tidings to the questioner, for the Prophet, peace and blessings be upon him, said: "A man from among those who were before you was brought to account, and nothing good was found in him except that he used to associate with people and was wealthy. He used to instruct his servants to overlook the debt of the one in hardship. [The Prophet] said: So Allah, the Mighty and Majestic, said to His angels: 'We are more deserving of that than him; overlook his [sins].'" Seek recompense for what you have done from Allah Almighty, and do not demand the debt you forgave from the man's heirs.