Steven Universe - Captain and crew by tree-bees

No, she's a gem. Gems are made, not born.
I think they referred to her as a mother because she was the biggest one of them all; combine that with her insect-like form and it only makes sense to call her that, even though she technically wasn't.

The little ones didn't have gems, they focused on this in Gem Glow. Those are probably just light constructs, like the gem's body.