Re: X-men Movie Timeline
^ Based on the information we were given, the only way for Alex and Scott to be brothers by DNA would be for their parents to have given birth to them more than 2 decades apart and then abandoned both of them n the same manner immediately after their births.
Having the same surname does not automatically indicate a familial relationship of some kind, BTW, and I know this from first-hand experience. I was one of three kids with the last name of Elmer in my high school and I am not related to either of the other kids with that surname in any way.
The similarity in powers could suggest some type of familial connection between Scott and Alex, but that doesn't mean that there HAS to be, or that said connection has to be direct.