My brother is a drug addict, and I do not want him to be buried in my grave.

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 'alyhi wa sallam, is His slave and Messenger.

A person should object, to the best of their ability, to the actions of evildoers like drug or alcohol addicts. The Prophet, sallallaahu ‘alayhi wa sallam, ordered whoever sees evildoing to change it with his hands; if he cannot, then he should change it with his tongue; if he cannot, then he should disapprove of it in his heart, and this is the weakest form of Faith. [Muslim].

If a person commits sins secretly then he should be objected to in secret and his sins should be covered up. The Prophet, sallallaahu ‘alayhi wa sallam, stated that whoever covers up the faults of a Muslim, Allaah will cover up his faults in this worldly life and in the Hereafter. [Al-Bukhari and Muslim] If a person commits sins openly, a person should object to him openly until he repents. Objecting to his sins may be done in many ways, including abandoning him, by not exchanging greetings, not visiting him if he becomes ill and similar acts that may deter him from committing sins, provided no harm is expected as a result.

If a sinner dies without repenting to Allaah, righteous people should abandon him after his death just as they abandoned him while he was alive. They should not follow his funeral procession or perform the funeral prayer for him, as the Prophet, sallallaahu ‘alayhi wa sallam, abstained from performing the funeral prayer of many sinners. They should also refrain from burying him in their private graves, unless absolutely necessary. Such measures should deter those like him from sinning. He should be buried in a public Muslim graveyard. 

If your brother takes drugs in secret, then you should cover his faulty behavior, bury him in a Muslim private or public graveyard, and supplicate to Allaah to forgive him. If he takes drugs openly, then it is permissible to refuse to bury him in your private grave; it is even recommended that you do this, provided that this is not likely to cause serious harm for you.

Please note that it is impermissible to bury two deceased persons in the same grave unless there is a necessity. If there is a choice and plenty of space, then there should be a separate grave for each.

You should also note that there is no effect if two people are buried in one grave in terms of one being affected by the other’s torment or bliss. Rather, each one will have his decreed punishment or reward. Allaah The Almighty Says (what means):

Allaah Knows best.