The first thing you should say when the parent tells you about encountering the food while cleaning out a sibling’s desk drawer is:
Oh my goodness! Are you okay?
Maybe you shouldn’t clean out his drawers next time.
When the parent responds by accusing you of harboring resentment from having your drawers cleaned out as a child and for not having any empathy, you should not say:
Well, I know you’re fine because we’re having this conversation right now.
You should then not try and backtrack your statement by saying the following:
When I say that you shouldn’t be cleaning out his drawers…I’m only looking out for you!
Saying all of the above might get you in what is colloquially known as “the dog house.”