Charlotte feels awful about calling her best friend, Kate, a big baby. Grandpa shows Charlotte his invisible mistakecase, a place where he keeps reminders of all the mistakes he never wants to repeat. Full color.

Even on beautiful days, bad things can happen. Bad things like Charlotte calling her best friend, Kate, a big pink baby, and Kate crying all the way home. Charlotte feels awful . . . in fact, she feels so awful she can't even eat her pizza and french fries. It was that bad.

Then Grandpa shows Charlotte his invisible mistakecase . . . and she doesn't believe her eyes It's a place where he keeps reminders of all the mistakes he never wants to repeat. Could Charlotte possibly have a mistakecase of her very own?