Why'd you leave the kids up on the table?

The story:

I was making an amateur music video to Chop Suey with my friend, and I told her six year old sister (she looks three, practically) to sit on the table. My friend said, "Why?" and I said "You know, 'Why'd you leave the kids up on the table?', that part. She's the kid," and my friend nearly died laughing. She eventually explained to me that it was keys, and we replaced her sister with keys.