The toothbrush
My 4 year old son came screaming out of the bathroom to tell me he'd dropped his toothbrush into the toilet.
So I fished it out and threw it into the garbage.
He stood there thinking for a moment, then ran to my bathroom and came out with my toothbrush.
He held it up and said with a charming little smile,
"We better throw this one out too then, cause it fell into the toilet a few days ago."