How do you deal with paternal and maternal uncles who do not check on the conditions of their deceased brother's children and leave them in poverty and need?

We advise the questioner to turn to Allah Almighty and ask Him to fulfill their need, while also employing the supplication taught by the Prophet, peace and blessings be upon him, to Ali, may Allah be pleased with him: "O Allah, suffice me with Your lawful provisions against Your unlawful ones, and enrich me with Your bounty, keeping me independent of all besides You." For Allah takes care of the one who has lost their provider. If relatives do not inquire about their conditions despite being able to, they are negligent and may incur sin, due to the obligation of providing for a needy heir-relative, and assisting those in need is a communal obligation (fard kifayah) upon Muslims. We also advise patience with relatives and maintaining ties with them even if they sever them; for that is better, and the one who maintains ties will have an helper from Allah against them.