In a recent interview with Guardians of the Galaxy director James Gunn with Entertainment Weekly, he reveals that two characters we were certain be simply rivals will indeed be blood-related! Well, not entirely blood-related, but they both were adopted by the same exact person!
“[Star-Lord] was abducted from Earth (Missouri) at age 8 and raised in a group of thieves and smuggles called the Ravagers. He’s good with the ladies and a little bit of a dick and very lucky. Thanos slaughtered [Gamora's] family and Nebula’s, then raised them together as siblings. They were bio engineered to become living weapons, so he’s really good at killing people.”
They've previously been described as having a "sibling-like rivalry" in the movie, but when they said sibling-LIKE, we didn't think they meant it as adoptive siblings! Though this connection certainly follows the storyline through Gamora's life in the comic books, this is a completely new take on Nebula's character who in the original went around the galaxy claiming to be Thanos's granddaughter.
This also brings up another important case: Nebula's character in the Infinity Gauntlet series actually ends up obtaining the infinity gauntlet, the item with limitless power, from Thanos. However, this means that this act of obtaining the gauntlet from the comics differs from any storyline the movies could portray because if she somehow obtains the gauntlet in a future movie, it would be an act of betrayal from her adoptive father.
From the context we've seen from Guardians so far, it seems that Gamora is the one abandoning Thanos's side while Nebula stays loyal. Undoubtedly, while they're battling it out in their ultimate girl fight scene, they'll have some sort of coinciding moral debate about leaving Thanos, their shared father.
Lastly, if Nebula ever did obtain the gauntlet in the film adaptations, its possible that she obtains the gauntlet as the turning point for her character, finally leaving Thanos like her sister Gamora did. Could this possibly be the finale to the Infinity Gauntlet storyline that Marvel has been teasing since the end of the first Avengers movie?
Believe it or not, it seems a lot more likely than you realize, as it was recently confirmed [Guardians of the Galaxy](movie:424073) will directly connect to [The Avengers 3](movie:738027) and Nebula's actress Karen Gillan recently told us that in order to prepare for playing her character in the movie, she went back and read the Infinity Gauntlet comics, which isn't even a storyline that connects to her story in the film very much.
Guardians of the Galaxy zooms into theaters on August 1st, 2014.