Is it permissible, Islamically, for the two sons to demand blood money (Diyya) 30 years after their father's death, claiming they were minors and are now in need, and do the uncle and whoever waived the blood money on their behalf bear a sin?

The uncle and relatives erred by forfeiting the father's blood money (Diyya) for the two orphans, which is an unlawful appropriation of an orphan's wealth. They must repent and return the rights to their rightful owners. The two orphans have the right to demand the blood money after this period, as rights are not forfeited by the passage of time. Whoever waived their rights did something they had no right to do.