In Heffley Family's house, Susan Heffley is dressing Rodrick Heffley up because she treats him like a baby but he doesn't want to. So Frank Heffley saw Rodrick's diaper is pooping & dirty but he's so gross for him until after Baby Draco's highschool...

Rodrick Heffley : STOP IT RIGHT NOW!!! crying like a bad baby loud

Susan Heffley (Rodrick Heffley's Mom) : No! undress him & changes him to baby shirt on

Frank Heffley (Rodrick Heffley's Dad) : Ew, he's very gross bad baby. Who should take care of him while we're work?