Naruto, at 18 minutes old, barely knows his father. All he knows is that there's a big yellow blob that feels safe. And that's good enough for him.
Naruto, at 3 and a half years old, wishes he knew his father. He hopes that his father loved him, but thinks that maybe his father hated him and he left him at the orphanage because there's something wrong with him. At night he dreams of a yellow haired man coming and telling him that he had been on some important mission, and he hoped Naruto could forgive him (which he would in a heartbeat), and that he was going to take him away from the awful orphanage to live with his family. And Naruto pretends that's good enough for him.
Naruto, at 10 and a bit years old, some times wonders about his father. Occasionally, when Iruka is away on a mission or teaching and the Hokage is busy, he wonders what it would be like waiting for someone who was actually related to him. Most of the time though he's to busy pulling pranks on (and with) Iruka, or talking to the Hokage or going to the academy to care about some guy who he's never known. And Naruto thinks that Iruka and the Hokage are good enough for him.
Naruto, at 13 and a quarter years old, doesn't know his father. Most kids, even orphans, know who their father was and what he did. Naruto doesn't. Naruto doesn't know that his father would be proud of him, or that his father would have smiled at his dream to become Hokage. But he doesn't care, because he found his surrogate father in his teacher, and his surrogate mother in his sensei, and his surrogate brother in his team-mate. And Naruto knows his makeshift family is good enough for him.
Naruto, at 14 and a fifth years old, finally knows who his father is. And he hates him, hates him with all his heart and soul. Not because he sealed the kyuubi into him (he understands that bit), or because it was in his name that he was shunned and abused for years (that's not his fault). No, he hates his father because of what he did to his family, to his Kakashi who he taught and left broken, to his uncle who was gutted when his student died, to his Iruka whose sister he killed. And Naruto knows that he will always hate his father, and that's good enough for him.
Naruto, at 16 years old, is more than slightly apathetic towards his father. He knows that one should feel more than that, that one should love or hate one's father, but he doesn't. He never really met his father, never really knew him, so when his name is mentioned it takes a second or two to realise that yes, he was related to him.
Naruto, at 18 years old, finally understands who his dad is. Not his father, the man who sired him, but his dad, the man who raised him since he was six, the man who loves him like his own son, the man who taught him the foundation of his ninja skills. His father may have given him life, and for that he was grateful to the man. But Naruto knew, without doubt, who his real dad was, and his face couldn't be found on the Hokage mountain. His dad's face could be found in the classroom, teaching the next generation how to be ninja, just like he taught him. And Naruto knows who his dad is, and that's all he needs to know.
