It is to go to the sacred House of Allaah The Almighty to perform specific rites in the month of Thul-Hijjah. It is one of the Pillars and obligations of Islam.
A Muslim, male or female, must perform the obligatory Hajj as soon as one is able to, and whoever defers it without a legal excuse is deemed sinful.
There are some conditions that must be fulfilled as prerequisites of performing Hajj: to be a Muslim, to be sane, to have reached puberty, to be free (not a slave), and to be able to perform it.
Performing Hajj and ‘Umrah for a little boy is accepted as a supererogatory act of worship.
As for a child under the age of discretion, his guardian can assume Ihraam (a state of ritual consecration during Hajj or ‘Umarh) and declare the intention to perform Hajj on his behalf. The guardian should stop the child from doing whatever acts which are forbidden during Hajj, and should perform Tawaaf (circumambulating the Ka‘bah) and Sa‘y (going between As-Safa and Al-Marwah) on behalf of the child while carrying him. The guardian is also to accompany the child to Mount ‘Arafah, Muzdalifah, and Mina, throwing the pebbles on his behalf.
However, if the child reaches the age of discretion, he can assume Ihraam and declare the intention to perform Hajj after seeking the permission of his guardian. The child is to perform whatever rites of Hajj he can do, and his guardian performs whatever the child is unable to do on his behalf, such as throwing the pebbles or the like. If the child is unable to walk, his guardian can carry him performing Tawaaf, Sa‘y, etc. still, the child must perform whatever he can perform himself, whether or not (he is) at the age of discretion, and it is impermissible to perform any rites of Hajj on his behalf as long as the child is able to perform it himself. Also, he should avoid whatever acts forbidden to be done by adults during Hajj.
The one capable of performing Hajj is that who can afford it both physically and financially, i.e. the one able to endure the journey and have enough money to go and return. One has also to be able to supply one’s children and whomever one financially supports, leaving them enough money until one returns. In addition, one has to settle all one’s debts and fulfill all one’s financial duties before heading for Hajj, provided the journey to Hajj is safe for the pilgrim’s life and possessions.
So, if a person can afford Hajj financially but not physically, such as being disabled by old age or an incurable chronic disease, one in this case may assign someone to perform Hajj on his behalf.
The person who performs Hajj on behalf of another must have performed Hajj on his own behalf first and should be given enough money to cover the costs of the journey back and forth.
There are some additional conditions for Hajj that are obligatory for women. A woman must be accompanied by a Mahramduring Hajj.
The Mahram of a woman should be her husband or any person unmarriageable to her forever, either by kinship such as a father, a son, a brother, a nephew, a paternal and maternal uncle, or by being unmarriageable to her for a legal reason such as a foster brother, a foster paternal uncle and the like, or by affinity, such as stepfather or a stepson, father-in-law and son-in-law.
A woman must cover the expenses of her Mahram during the journey of Hajj. Therefore, a woman is not obliged to perform Hajj until she has enough money to cover her own and her Mahram’s expenses of back and fro.
If a woman finds a Mahram yet she delays performing Hajj, out of negligence, until she lost him while she still possesses the financial capability, she has to wait until she finds another Mahram. However, if she has lost hope in finding another Mahram, she is to find someone to perform Hajj on her behalf.
If someone is obliged to perform Hajj but he died before doing it, an amount of money, enough to cover the Hajj expenses, should be taken out of the capital of his inheritance and given to someone to perform it on his behalf.
When someone performs Hajj on behalf of another, the latter becomes no longer obliged to perform it. It is as if he has performed it himself. In this case, the one performing Hajj for another is called a ‘deputy pilgrim’. Upon performing Hajj on behalf of another, a deputy pilgrim should have the intention of performing Hajj on that person’s behalf, and he is to recite Talbiyah also on his behalf; it is sufficient to make the intention to perform the rites of Hajj on someone’s behalf without mentioning his name. However, if the deputy pilgrim forgets the name of the person on behalf of whom he is performing Hajj, he can declare the intention and recite Talbiyah on behalf of the one who has given money to perform Hajj on his behalf, without mentioning his name.
 Mahram: A woman’s husband or any unmarriageable kin of hers. (Translator)