This slider is controlled by moving up/down on the foot in side view. I recommend combining with the belly, waist and hip sliders to create your ideal shape. I purposely made this to be combined with the belly growth from pregnancy, so by itself the slider just gives your sim a gut. IMO it moves the belly into the twins/triplets range while staying somewhat realistic.
(January 14, 2020, 11:11 am)kirax12 Love all the sims you've shown off! I created an additional belly slider a few months back based on my personal preferences for a heavy beachball belly.