All perfect praise be to Allah. Blessings and peace be to upon Prophet Mohammad and upon his family and companions.
Tawaf is a pillar of Hajj, and it is a condition for its validity that the person performing it makes the Ka`bah on his left during its entire rounds. If this condition wasn`t met :
The Shafi`ite jurists state that such Tawaf is void and unaccounted for. Al-Imam Ar-ramli said: “If he made the Ka`bah on his right and walked before it, or faced it, or made it to his back and performed Tawaf while his chest was against it; or he made it on his right, or left and walked backwards, then his Tawaf is void because performing it that way wasn`t mentioned in the Islamic Sharia.” {Nehayat Al-Mohtajj Ela Sharh Al-Menhajj vol.280/pp.3}.
If this Tawaf wasn`t accounted for, then it is an obligation on the person in question to make up for it, even after years, since it is a pillar of Hajj. In line with the above question, if the child had performed the acts of his Hajj: stoning the pebbles at Jamrat al-Aqaba and shaving, then he is in a state of First Tahalull (Lifting the restrictions of Ihram except having sex with one`s wife), and since he hasn`t reached puberty, it is imperative on his guardian to send him back to Ka`bah to make up for the Tawaf so as to complete the acts of his Hajj even if that be after so many years.
As regards the Hanafite School of Jurisprudence, if he didn`t make the Ka`bah on his left during the Tawaf, then he is obliged to re-perform the Tawaf in case he was still in Mecca, or else it is imperative that he offers a sacrificial animal. It is stated in [Ad-dur Al-Mokhtar] and [Hasheiat Abn Abdin vol.494/pp.2]: “ The Ka`bah becomes on his left…..If he made it on his right, then he is obliged to re-perform the Tawaf so long as he is in Mecca. But, if he returned to his country, then he is obliged to offer a sacrificial animal, and the same applies if he had started the Tawaf from a place other than the Black Stone.” And Allah Knows Best.