I watched a theory that I scoffed at...I'll put it in tags again but it does draw from a prequel element
There was a theory that Rey was born Anakin Skywalker style. No father. The force created her, she is a manifestation of the same force energy that created Darth Vader...I thought it was pretty stupid. But it doesn't sound as stupid anymore
I like this one way more:
Immaculate force baby would be the worst possible option IMO.