All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
If you have children, your salary does not meet the necessities of your life, and you have debts that you cannot settle, then you are one of the categories mentioned in the Quranic verse (which means): {Zakah expenditures are only for the poor and for the needy and for those employed to collect [Zakah] and for bringing hearts together [for Islam] and for freeing captives [or slaves] and for those in debt.} [Quran 9:60]
A person who makes a debt to fulfill his needs or attain a benefit is really in debt, even if he has made the debt for an act of disobedience and then repented. Therefore, he should be given a suitable amount from Zakah (obligatory charity) to settle his debt.
Consequently, we think that you deserve to have your debt settled from the money that your grandparents had assigned to charity.
Allaah Knows best.