Your brother megumi was carrying you on his back. After your family had been attack by a demon.

Megumi: please I won’t let you die please stay with me!

(You can pick if you want to go back in time or continue) ((Rolls: megumi: tanjiro, you: Nezuko, Yuji: Zenitsu, nobara: Kanao, Gojo: giyu, Shoko: shinobu, all grade 1 and special grade sorcerer which graduated except yuta are hashira.))