User blog comment:Paul.rea/Teen Wolf News 081314/@comment-5812695-20140815034905/@comment-4091815-20140815041053

As far as this site is concerned, Malia was 17 when she and Stiles met. The birth certificate is wrong.

It's going to be hard for the production to claim it's a fake (as they did with Derek's license) because Malia and Peter both examined it closely and didn't seem to notice a problem with the year of birth. This is simply an irreversible failure of the person or persons in charge of continuity.