The one picture that was released by Fox to promote Days of Future Past that has caused the biggest stir had to be that pic of Quicksliver with the little girl in his lap. Now, to most, this seemed to be a reference to his sister, the Scarlet Witch. Then, the ire from the fans began as they believed the little girl to be Quicksilver's sister. That was put to rest months ago when Singer told the press that this was NOT true and that the Scarlet Witch would not be making an appearance.
When asked by EMPIRE magazine if the little girl was Scarlet Witch, Singer answered, ""Is that the Scarlet Witch? No, that's his little sister,"
BUT there does seem to have been a reference to the missing twin in the script.
Singer revealed. "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 bool fans. I ended up cutting it."
I don't know. I think that line would have been awesome, personally.
When asked about Evan Peters' involvement in the announced sequel, X-Men: Apocalypse, and he had this response:
"Even though our Quicksilver is not a main character like in The Avengers, it's a character there's a lot of thought and concern about and it's a character I'd like to explore further in the sequel."
The court's still out on whether the fans really want to see Pietro after DoFP or not. Or if they really want to see Fox attempt the twins at all after what Marvel has released and, especially, after Avengers: Age of Ultron comes out. I'm willing to wait and see, myself. But, although some fans are willing to give a shot, they have a hard way to go selling their version of the Mutant speedster.