If his family offer an udhiyah on his behalf whilst he is on Hajj, does he have to offer another udhiyah?
Question

                I have a friend who told me that his family is going to offer an udhiyah on his behalf. If he does Hajj, does he have to offer udhiyah again?
Praise be to Allah.The pilgrim is not obliged 
    to offer an udhiyah and it is not prescribed for him to slaughter it in 
    Makkah. Rather what is required and prescribed in his case is to offer the 
    hadiy. If he  does Hajj Tamattu’ or Qiraan, then he must offer the hadiy, 
    which is a sacrifice which must fulfil the same conditions as the udhiyah, 
    because offering a sacrifice is obligatory for those who are doing Tamattu’ 
    or Qiraan. If he cannot afford to offer a sacrifice then he must fast for 
    ten days, three days during Hajj and seven days after he returns to his 
    homeland, as Allaah says (interpretation of the meaning):
“and whosoever performs 
    the ‘Umrah in the months of Hajj, before (performing) the Hajj, (i.e. 
    Hajj-at-Tamattu‘ and Al-Qiraan), he must slaughter a Hady such as he can 
    afford, but if he cannot afford it, he should observe Sawm (fasts) three 
    days during the Hajj and seven days after his return (to his home), making 
    ten days in all”
[al-Baqarah 2:196]
For the one who is doing 
    Hajj Ifraad, he does not have to offer a hadiy, but he may do so 
    voluntarily. The Prophet  (peace and blessings of Allaah be upon him) 
    offered a hadiy of one hundred budnah (camels) during his Hajj. 
The point is that whether 
    his family offers an udhiyah on his behalf or not, it is not recommended for 
    him to offer an udhiyah so long as he is going to go for Hajj. 
Secondly: 
If the pilgrim leaves his 
    family in his homeland, it is prescribed for him to leave them money so that 
    they can offer an udhiyah. 
Shaykh Ibn ‘Uthaymeen (may 
    Allaah have mercy on him) was asked: How can a person combine udhiyah and 
    Hajj, and is that prescribed? 
He replied: The pilgrim 
    does not offer an udhiyah, rather he offers a hadiy. Hence the Prophet  
    (peace and blessings of Allaah be upon him) did not offer an udhiyah during 
    the Farewell Hajj, rather he offered a hadiy. But if we assume that he is 
    doing Hajj by himself and his family are in his homeland, then in that case 
    he should leave his family enough money to buy an animal and offer it as an 
    udhiyah, so he will be offering a hadiy and they will be offering an 
    udhiyah, because the udhiyah is only prescribed in places other than Makkah, 
    but in Makkah it should be a hadiy. End quote from al-Liqa’ al-Shahri. 
And Allaah knows best.