making Hajj for his mother, forgot to pronounce the intention
appropriately reference this fatwa to: www.fatwa-online.com,
What is the ruling concerning the one who performed Hajj on
behalf of his mother and at the meeqaat he pronounced the
talbiyyah for the Hajj and did not do so for his mother?
As long as his intention was for the Hajj on behalf of his
mother, even if he forgot, the Hajj is (acceptable) for his
mother since the intention is a stronger (argument), for that
which the Prophet (sal-Allaahu
`alayhe wa sallam) said: ((Actions are but by intention)).
So if the intention in his coming was for Hajj on behalf of
his mother or father and he then forgot when he entered the
state of ihraam, the Hajj is (acceptable) for whoever he had
intended it for, either his mother, father or other than them.
Majmoo' Fataawa Samahatu ash-Shaykh Ibn Baaz - Volume 6, Page
116, Fatwa No.74