Measurement Error

A few nights back, as Ben and I were silently laying in bed waiting for sweet sleep, Ben said, "Dex was in the bathroom today and he said, 'Daddy, it's 16 squares from the toilet paper roll to the bathtub.'" I burst out laughing imagining the bathroom scene with Dex pulling the toilet paper over to the tub and counting the squares. Then Ben said, "And then Dex said, 'Daddy, the potty is clogged.'" The next day when I was home with Dex, he went to the bathroom and announced from behind the closed bathroom door, "Mommy, it's 22 squares from the toilet paper roll to the bathtub."  "Don't put that in the toilet!" I shouted. We're proud that he figured out how to use the toilet paper squares as a unit of measurement but I'm a little concerned about the size of his measurement error.