Soo. One day, a demon invaded the Headquarters so the Hashiras went to go kill it, by in the process, they got turned into babies after Gyomei killed the demon. So Kagaya got the Kamaboko squad to watch over them until the demon blood art wears off.

When the Kamaboko squad arrived, they saw that every one of the Hashiras were toddlers now, the youngest being Muichiro, who was a 7 month old baby.

Shinobu was poking Giyuu, Gyomei was still praying as a toddler, Tengen and Rengoku were playing together, Obanai and Mitsuri were talking, and Sanemi was sitting by himself.

Genya : “Oh my god..”

Zenitsu : “C-Children??”

Nezuko : “Mm!” Translated: “Oh my!”

Inosuke : “Ew, kids?”

Tanjiro : “Aww! Look how small they are!”