To whose record are the good deeds of prepubescent children added?
Praise be to Allaah
The reward for the deeds of a child who has not reached puberty – meaning his good deeds – go to the child himself, not to his parents or anyone else, but his parents will be rewarded for teaching and guiding and helping him to do good, because of the report in Saheeh Muslim from Ibn ‘Abbaas (may Allaah be pleased with him) who said, “A woman held up a boy and said, ‘O Messenger of Allaah, will his Hajj be counted?’ He said, ‘Yes, and you will have a reward.’” (Reported by Muslim, 2378)
The Prophet SAW (peace and blessings of Allaah be upon him) stated that the Hajj would be counted for the boy, and that his mother would be rewarded for taking him on Hajj.
Similarly, people other than the parents may also be rewarded for good deeds, such as teaching those under their care such as orphans, relatives, servants and other people, because the Prophet SAW (peace and blessings of Allaah be upon him) said: “Whoever guides others to do good will have a reward similar to that of the one who does it …” (reported by Muslim in his Saheeh, 3509), and because this is a form of co-operating in righteousness and piety, which Allaah urges us to do.
(Fataawa Islamiyah, Ibn ‘Uthaymeen, 526).