A new Final Fantasy 7 Remake fan theory makes a distressing amount of sense. I'm not usually one for insane theories, but this one concerning Aerith almost sounds too good to be true. Be warned, there are spoilers for the ending of Final Fantasy 7 Remake here!
The extensive theory was posted over on the Final Fantasy 7 Remake subreddit. In short, the theory posits that Aerith is aware of the events of the original game, like Sephiroth, and has either time-traveled in a very roundabout way (also like Sephiroth), or has been sent a message through the Lifestream by Aerith from the original game, warning her of things to come.
The theory hinges on two pieces of evidence. One: Aerith knows Marlene is Barret's child without ever being told (something even Tifa picks up on). Two: Aerith knows Red XIII is a child in Hojo's labs without ever being in contact with him, something that wasn't revealed in the original game until you met with Bugenhagen in Cosmo Canyon.
The fan theory is very meta, and entirely within the realms of something Tetsuya Nomura would pull. The theory ultimately suggests that Aerith will sacrifice herself to cast Holy, and will tell Cloud and company that Sephiroth needs to be stopped at all costs. I'll admit, mulling this theory over I'm more drawn to it than I initially was, and it's something that would radically alter part two of the remake (which I think is going to be drastically different than everyone expects from the original game).
This is Tetsuya Nomura's world, we're just living in it. There's still a good few years at least until we're playing part two of the Final Fantasy 7 Remake saga, even if it is already in production.