How should the questioner act regarding her money that her guardian placed in interest-bearing bank certificates without her consent, and does she bear any sin for that?

If the mother has not yet taken out the usurious loan, she should be deterred from doing so, and its prohibition should be explained to her, as well as the prohibition of investment certificates in usurious banks.

If she has already taken out the loan, the questioner may take only her principal, and dispose of the usurious interest by spending it on charitable causes and public welfare. She may also benefit from it to the extent of her need if she is poor.

If the mother wishes to invest money, it should be done through legitimate means via Islamic banks.

However, if the mother has taken out a loan with usury, she should be advised to make sincere repentance, and it is permissible to benefit from the loan amount itself.