Praise be to Allah.
Hajj and ‘Umrah are separate rituals. The Prophet (peace and blessings of Allaah be upon him) explained how to do them qiraan (‘Umrah and Hajj together), ifraad (Hajj on its own) and tamattu’ (‘Umrah and Hajj with a break in between). If a person wants to enter ihraam for ‘Umrah on behalf of his mother, for example, then enter ihraam for Hajj after exiting ihraam for ‘Umrah and do Hajj on behalf of his father, or vice versa, he may do that. If he enters ihraam for one of the two rituals on behalf of himself, then after exiting ihraam, he enters ihraam for the other on behalf of his father, for example, that is permissible, because actions are but by intentions, and each person will have that which he intended. End quote.