Go deep enough into the internet and you'll find the most casual, logical theories just sitting there. A redditor named /u/Patojavier has noted that 'Rey' is the Spanish word for 'King', and Daisy Ridley looks a bit like Natalie Portman, who played Padmé, one-time Queen of Naboo, in the prequel trilogy. You can see the conclusions being drawn here. If Rey is indeed a Skywalker, then 'Rey' most likely isn't her true name. Using the George Lucas Rule of Poetry and Rhymes, if Kylo Ren was an alias for Ben Solo, you can be damn well sure that Rey is a cover for something else. If Luke is her father, then it stands to reason that he would name her after the mother he never knew as a tribute of sorts; and subsequently if he wanted to hide her, why not get clever with the assumed name? It's not like there's a history of insanely clever pseudonyms floating around the Star Wars universe; Obi-Wan didn't even bother to change his last name after taking the name Ben, for chrissakes. It's ever more fuel to the speculative fire, and if you want to believe that Spanish is an ancient language that exists in a galaxy far, far away, then it's your prerogative to believe this theory if you want to. There are crazier ones out there. Rey Plagueis, for example.
Cinephile since 1993, aged 4, when he saw his very first film in the cinema - Jurassic Park - which is also evidence of damn fine parenting. World champion at Six Degrees of Separation. Lender of DVDs to cheap mates. Connoisseur of Marvel Comics and its Cinematic Universe.