Enable the boolProp testingCheatsEnabled true code to be able to raise and lower your Sims motives by clicking and dragging a specific motive bar either up or down. First, your child must be a toddler and you must own a potty chair. Pick up your toddler or simply click on the potty chair and select "Potty Train..." and the toddler you want to potty train (if you have more than one toddler). When your Sim puts the toddler on the potty chair, click and drag the toddlers Bladder motive down to the red area. The toddler should use the potty chair as soon as the motive gets low enough. When he or she is done, your Sim toddler is now potty trained.