Pretty much I sum it to luck of the genetic dice... the same thing that gifts you with big or small boobs... When in doubt, fill it out! With surgery lol. They have places that'll do butt & hip implants, but of course buyer beware. I know Dr. Cardenas does some of these procedures with his team of helpers... feel free to look him up. I'm positive there are a ton of others too. What nature didn't gift you, science can grant you.