Several months ago a photo was released that featured Evan Peters as Quicksilver and a young girl in pink. Most assumed this was Quicksilver's (In the comics Twin) sister Wanda Maximoff aka Scarlet Witch. Bryan Singer now reveals to Empire (via CBM) that actually she is not Wanda but Wanda's little sister. He goes onto say that an Easter egg that has since been cut from the film revealed that Quicksilver actually has two sisters in this film:
"Is that the Scarlet Witch? No, that's his little sister. I even had a line which I cut, where Quicksilver's mother says to the little girl, 'Go up and bug your sister,' and the little girl says, 'She bugs me!' You never see the older sister, but it was to imply that there is an older sister for comic book fans. I ended up cutting it."
Maybe the little girl in Days of Future Past is actually Polaris!? You know Wanda's and Pietro's other sister.
X-Men: Days of Future Past hits May 22nd