Would you like some spoilers to go with these spoilers? I'm just heating up some spoilers on the spoiler.
It used to be fun and hip to speculate about Jon Snow's parentage. But at this point if you're not sold on R+L=J, you're only deceiving yourself (or for some reason you don't devote huge blocks of time to reading Game of Thrones fan theories... in which case, how did you get here?).
"R+L=J," of course, obviously, as everybody knows, is the theory that Jon Snow's true parents are Rheagar Targaryen and Lyanna Stark. Now, as we all learned in elementary school, after Rhaegar was killed in battle by Robert Baratheon, the new king sent Ned Stark and Howland Reed to retrieve Ned's sister Lyanna Stark from the Tower of Joy. According to lore (aka nerds), Ned found Lyanna in a bed of blood, implying she might have just given birth. Her last words to Ned were "promise me," which most people have interpreted to mean "promise me you'll protect and hide the identity of my baby, this Targaryen-Stark hybrid who shall hereafter be known as Jon Snow."
But have you ever thought about if there were two babies? WHAAA? Yeah. And what if Ned Stark and Howland Reed each took one? And that other one was Bran's cool older friend Meera Reed? Just to be clear, I'm saying that Jon Snow is the Ashley and Meera Reed is the Mary-Kate. A lot of people are commenting that this theory is similar to Star Wars, but I see strong shades of It Takes Two.
What's the "evidence"? Well, there's the above photo comparison, which does emphasize the pair's similarly scraggly bob hairstyle. Could it run in the family? They also are the same age, even though Meera seems like a badass rebellious teenager. Apparently it says in the appendix to A Clash of Kings that they both were born in 283 AC. (If GRRM has to brainstorm imaginary birthdays for every single character in the GoT world, no wonder it takes him so long to write a book.) Also, even though Ned Stark and Howland Reed were such close friends, Reed never visited Winterfell after the whole Tower of Joy fiasco. Was it the kind of thing where you share a dark secret with someone and then you can't hang out with them because there's a Targaryen elephant in the room?
So many questions. Crazy. You know what's even crazier, though? Our future selves after we find out all the answers, because we won't know what to do with our time anymore.