Do the heirs have to get rid of interest/riba?
Question

                My father has passed away and left a wealth for us in a governmental bank. Interest has been added to this money since he firstly put it in the bank 1986 until he died in 2005. After my father died I cancelled the interest, and now I am trying to get rid of it. 

My question is: Do I have to get rid of all the interest that was added since the money was firstly put in the bank, or only the interest of the last one or two years before I cancelled it?.
Praise be to Allah.It is not permissible to 
    put money in riba-based banks except in cases of necessity in order to 
    protect it when there is no Islamic bank. In that case one should only use a 
    current account (i.e., without interest), on the basis of doing the lesser 
    of two evils. The interest that is taken for depositing money in a 
    riba-based bank is haraam and it is riba which has been forbidden by Allaah 
    and His Messenger in emphatic terms. Hence you should get rid of it by 
    spending it in the public interest and on charitable causes. See the answer 
    to question no. 20876 and
    45691. 
This getting rid of it is 
    obligatory for the one who dealt with riba. As for the heirs, they may 
    benefit from this money according to some of the scholars, because that 
    which it is haraam to acquire – such as riba – is haraam only for the one 
    who acquires it, not for the one to whom the money is transferred by 
    permissible means such as inheritance, a gift and so on. 
Shaykh Ibn ‘Uthaymeen (may 
    Allaah have mercy on him) said: As for that which is haraam because of the 
    way in which it is acquired, it is haraam for the one who acquires it, such 
    as riba. If the person who dealt with riba dies, then his wealth is 
    permissible for his heirs. As for that which is haraam in and of itself, 
    such as alcohol, it is haraam for the one who passes it on and the one to 
    whom it is passed on. The same applies to that which is haraam and remains 
    haraam, such as usurped and stolen property. If a person steals something 
    then dies, it is not permissible for the heir. If he knows who the owner is 
    he should give it to him, otherwise he should give it in charity on his 
    behalf. End quote from Liqa’aat al-Baab il-Maftooh (1/304). 
Based on this, there is 
    nothing wrong with you benefiting from this wealth, but it should be noted 
    that you have to get rid of the interest that was added to the money after 
    your father died, because the money came into your possession on the death 
    of your father. As for the interest that your father took during his 
    lifetime, there is nothing wrong with you benefiting from it, and you do not 
    have to get rid of it. 
Some scholars are of the 
    view that riba-based interest should not be included in the estate, and that 
    one should get rid of it. This was stated in a fatwa by the scholars of the 
    Standing Committee for Issuing Fatwas. 
See: Fataawa al-Lajnah 
    al-Daa’imah (16/455, 479). 
But the former view is the 
    one that we favour and follow. 
And Allaah knows best.