This is a fan theory about Bumi, Aang and Katara’s eldest son.Spoiler Warnings for both shows. For those of you who aren’t aware, Bumi is the eldest Son of the late Avatar Aang and Katara. He is the only one to not be born a bender. His sister, Kyais a water bender and the baby Tenzin, the first air bender to be born after the 100 year war and genocide of the air nomads.
So why was Bumi born a non-bender? One theory us that Bumi was born premature. But this is not my theory. It is plausible but here’s what I have come to believe.
Before Zuko taught Aang to fire bend properly, we have the deserter. This is one of my favorite episodes of the original show. In this episode, Aang is anxious to learn fire bending and his recklessness causes him to meet Jeong Jeong. It’s not said, but I think he has PTSD. In any case in his recklessness, Aang while attempting fire bending burns Katara. I think Tenzin never knew about this because of his love for his father but this is why I think Bumi didn’t become an air bender until after Harmonic Convergence. I leave you with the scene where Bumi air bends,