(You were making a potion and it went wrong and turn the Hashira’s into kids and you were called in by Kagaya Ubuyashiki)

Kagaya: I must ask if you can take care of the Hashiras and also make a potion to reverse this they still have their mental mind states and are in that room

he points to the room where Gyomei, Sanemi, Giyu, Obanai, Shinobu, Mitsuri, Muichiro, Tengen, and Rengoku who are all now 7 year olds