Is it better to repeat Hajj for himself or to do Hajj on behalf of his relatives?
Question

                Is it better for a person to repeat Hajj for himself on a voluntary basis, or to intend that it be on behalf of one of his relatives who have died or who are alive but are unable to perform Hajj some years? i.e. if he does Hajj for himself one year then intends the Hajj in the following year to be on behalf of one of these relatives?.
Praise be to Allah.
    It is better for him to do Hajj on his own behalf, because 
    this is the basic principle, and he can make du’aa’ for himself and for 
    others among his relatives and all the Muslims. But if one or both of his 
    parents did not do the obligatory Hajj, then he may do Hajj on their behalf 
    after doing Hajj for himself, as a way of honouring them and treating them 
    kindly when they are incapacitated or after they have died. But he should do 
    Hajj or ‘Umrah for each of them separately; he cannot combine them both in 
    one ‘Umrah or one Hajj. End quote. 

    Fataawa al-Lajnah al-Daa’imah, 
    11/66 

    Shaykh Ibn ‘Uthaymeen (may Allaah have mercy on him) was 
    asked: A woman wanted to do Hajj on behalf of her mother who had died, but 
    her mother had done the obligatory Hajj. Which is better: to do Hajj on her 
    behalf or to make du’aa’ for her? 

    He replied: 

    It is better for her to do Hajj for herself, and to make 
    du’aa’ for her mother, because the Prophet  (peace and blessings of 
    Allaah be upon him) said: “When a man dies, all his good deeds come to an 
    end except three: ongoing charity (sadaqah jaariyah), beneficial knowledge, 
    or a righteous son who will make du’aa’ for him.” He did not say: a 
    righteous son who will do Hajj on his behalf or fast on his behalf or give 
    charity on his behalf or pray on his behalf. If someone were to ask us: 
    which is better, to pray and give the reward to my father, or to give 
    charity and give the reward to my father, or to make du’aa’ for my father? 
    We would say: it is better to make du’aa’ for your father, because the 
    Messenger  (peace and blessings of Allaah be upon him) knew more than 
    us, and was more sincere than us, and more eloquent than us, and he did not 
    say, a righteous son who will do good deeds on his behalf; rather he said: a 
    righteous son who will make du’aa’ for him. This is what the Prophet  
    (peace and blessings of Allaah be upon him) taught us. End quote. 

    Fataawa Ibn ‘Uthaymeen, 21/251.