9Caillou no longer wants to wear diapers - even at night. Caillou knows now when he has to use the potty. Very soon, he hopes to use the big toilet and to no longer wear diapers at night. A parent's wish to have their child totally potty trained is not necessarily in line with the physiological capacities of their child. This book helps to understand that it is not parents who potty train their child but rather the child who does it on their own.