Zuko's pain and his relationship with his Uncle Iroh who is
his Mentor ,his Substitute Father figure to Zuko
whom him selfs Loves Zuko as if he was his Son
{His Son Died in Battle}
he Teaches Zuko the art of bending and guiding the power of lightning and takes care of Zuko when he is broken and I'll and nurces him back to health eventually zuko teams up with his sister Azula and betrais his uncle disapointed Iroh turns away from his nephew and refuses to speak to him
Zuko is taken back from exile and restored as Fire Prince
Zuko's guild builds up and frequently visites his uncle whom still refuses to speak to him untill eventually he breaks his silence and does this to tell Zuko that
Avatar Roku is his maternal Great-grandfather.
He tells Zuko that he might be able to redeem their family and that he can restore balance in the world,

signifying that although his nephew had betrayed him,
he still had faith in Zuko. He then gives Zuko a crown which Sozin once gave to Roku a royal artifact to only be worn by the crown prince of the Fire Nation

Zuko realizes that Iroh was more of a father to him
and atemptes to break him out but Iroh escaped before Zuko arived Zuko expresses his guilt over betraying his uncle on several occasions after joining Team Avatar. Prior to the arrival of Sozin's Comet, Zuko learns that Iroh is the new leader of the Order of the White Lotus, and that his uncle intends on liberating Ba Sing Se. Zuko reunites with his uncle before the final battle, and sobs as he begs for his uncle's forgiveness. Iroh embraces his nephew in an emotional hug, stating that he was never angry with Zuko, just sad that he had lost his way, and is now happy that Zuko found his way to him. He is proud to find that Zuko has finally found peace with himself and his destiny, and the two finally make up.

Before departing to fight Azula, Zuko asks if Iroh will accept his rule as Fire Lord. Iroh says no, as Zuko is the far more suitable heir: An idealist with a pure heart. Zuko is unsure due to his history of misdeeds, but Iroh assures him that since Zuko has learned from his mistakes, he will know how to rule as a man of peace and love. Zuko is emboldened by his Uncle's wise words