A man in his forties passed away from cancer, leaving behind a wife and two underage children. He had not performed his obligatory Hajj during his lifetime even though he had the means. After his death, one of his sisters performed Hajj on his behalf from her own money as she wanted to leave the whole estate intact to his children. Is this permissible?

Hajj is one of the pillars of Islam

- Allah Almighty says:

"And [due] to Allah from the people is a pilgrimage to the House-for whoever is able to find thereto a way. [Qur`an 3:97]
-The Prophet [pbuh] said: "Islam is based on five things: Testifying that there is no god save Allah and that Mohammed is His Messenger, performing prayers, giving zakat, making Hajj and fasting [the month of] Ramadan" [Bukhari and Muslim].
Among the conditions for the obligatoriness of Hajj, is the ability of undertaking this duty as mentioned in the Qur`an and Sunna of the Prophet [pbuh]. Since this is not only restricted to financial means but also includes a person's physical ability and safe journey among others, the Prophet said: "Whoever refrains from making Hajj while he has provisions and safe means for traveling will die as a Christian or Jew" [Al-Tirmidhi].
Hajj, which is obligatory, is among the acts of worship that may be executed in another's stead. Amr ibn Aws narrated from Abu Razin al-'Uqali that he approached the Prophet [pbuh] and said, 'O Messenger of Allah! My father is an old man and cannot make Hajj, `Umrah or travel." The Prophet [pbuh] replied, 'Make Hajj and `Umrah on behalf of your father' " [Al-Tirmidhi and Abu Dawud].

Conditions for making Hajj on behalf of another
A person who makes Hajj on behalf of another must have previously made his own obligatory Hajj. Ibn Abbas narrated that the Prophet [pbuh] heard a man say, "O Allah! Here I am in response to Your call on behalf of Shubruma." He asked him, "Who is Shubruma?" The man replied, "A brother or close relative." The Prophet [pbuh] then asked him, "Have you made your own Hajj?" The man replied in the negative, whereupon the Prophet [pbuh] said, "Perform your own Hajj first and then make Hajj on behalf of Shubruma" [Al-Tirmidhi]. Hajj is an obligatory act of worship that may be delayed and not something to be undertaken as quickly as possible.

The Ruling

The Hajj which the sister of the deceased made out of her own expenses on behalf of her brother is permissible and he will receive its reward by the will of Allah. There is no objection to this based on the hadith narrated by Abu Hurayra, may Allah be pleased with him, which states: "When a man dies, his work comes to an end except for three things: an ongoing charity, knowledge benefitted from or a pious offspring who prays for him" [Al-Tirmidhi].

Allah Almighty knows best.