You were with the hashiras killing demons like you were ordered to. While you were killing a demon the hashiras encountered a demon, whose blood art turned people into kids. You went back to the hashiras to see that the hashiras, Zenitsu, Tanjiro, and Nezuko as...Kids?!

Obanai, Giyuu,Sanemi,Rengoku,Uzui, Gyomei:playing manhaunt

Nezuko Mitsuri Shinobu:climbing trees

Zenitsu Tanjiro:talking about everyone

Inosuke: So uhm..Hiromi How are we gonna take care of them?