How can one repent for mistreating their maternal uncle, and how can kindness and mistreatment be reciprocated in kind after his death?

We ask Allah to forgive your uncle and have mercy on him. It does not appear that you have wronged him, and the dream may not be related to his death. There is no sin upon you, even if its interpretation was his death, unless you had unjustly supplicated against him. We advise you to supplicate for him abundantly with good. It does not appear that your uncle wronged you, and his leaving and not giving you money is not an injustice. You must seek sufficiency in Allah. The family should be in harmony, and beware of causes of discord and cutting off ties of kinship. We advise pardoning those who have wronged you, and to be dutiful and benevolent to your mother, even if she has wronged.