Crazy toddler may sit on this (5)
I believe the answer is:
potty
'crazy' is the definition.
(I've seen this before)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for potty that I've seen before include "Bonkers" , "sort of chamber?" , "Mad" , "Nuts" , "Where kids go" .)