The phrase "small potty" generally refers to a small-sized toilet, usually designed for young children who are learning to use the restroom independently. Full definition
A bulk pack of small potty pads have 150 pads in a box and you receive a bigger discount for buying the potty pads in bulk. (modernpuppies.com)
If he is afraid of the big toilet, buy him his own smaller potty to help him get over any fears that are holding back his success. (howtoadult.com)
He uses small potties and the toilet (since 6 months old or so) and before that a special EC potty or hovering techniques of all kind. (babycenter.com)