Hourglass and weight ...
The great thing about Sierra is that she has a full, perfect hourglass. So no matter what weight I've ever seen her at -- thinnest or fullest/widest -- her hourglass kept her slender. All the added weight seemed to go into her hips or bust.
That's eternal perfection.
She's still my all-time favorite African-American starlet and I'd be hard pressed to pick any other woman on this planet that wouldn't be the ultimate lover. That body and presence on-film -- heck, just even if she was only a nude model without the "action flicks" -- is one of the greatest crafted by God.
And that's why she stays eternally beautiful, regardless of age or weight.