[There are spoilers ahead for this season of Grey's Anatomy. If you're not caught up yet, you might want to exit this post!] Obviously, many people really close to Meredith have passed away in the show's 17-season run, so it could be an entire group of people.
Like, the list is long as hell. And because the clip showed her reuniting with this person on the beach, it's safe to assume it's someone who is also dead.
The frontrunner, as far as the fans are concerned, is Lexie Grey. There's not a lot of proof that it'll be Lexie, but that's who the fandom seems to want it to be the most.
Read more on cosmopolitan.com