Okay so it is pretty high on demand for more Steven Universe theories and I may just give you one.

Pearl:
In the episode where Jasper comes to Earth we hear some things about the gems

Amethyst: an peewnie overgrown runt
Garnet: A sad display
Pearl: A lost defective Pearl..

We can tell by this info of Pearl that
A) There is more than 1 of her
B) That she is lost?
C) That she is defective....

This brings up a lot of questions left unanswered and I am here to help.
A) By the way she acts, like all ways cleaning up, a teacher of sorts, knows lots about gems and fighting, and that she can make a plan that is pretty accurate and would help. This would possibly make her a gem slave/house keeper/tuter for young gems. Interesting...

B) Considering that she is on Earth and not in homework we can say that this applies to her location, not something else.

C) We'll this is harder for me too break down, so I'm leaving this blank for now.

Well defective is hard to go at but I think I can crack the case. Rose had a Pearl to do things for her when she started to malfunction. Rose decided to try and use her healing powers on the Pearl and it made her heal into a real gem and not a work animal. Amazed by this she sent out to try and heal others like her until homeworld gems started building on Earth. Upset by this she fought for the planet and won with her shield. You already know the rest, but remember that's just a theory. A STEVEN UNIVERSE THEORY! Thanks for reading❤

Comment and message for particular theories you want me to touch up on and make sure to put your input on the Theory to add to it or change it. BYE!!