Not to denigrate their achievement, but as CZ points out, who says that it takes two years to get a PPL? There are so many variables (
viz.: money; weather; instructor, student and aircraft availability; instructor and student ability) that I don't believe it makes any sense to say that the course of instruction 'normally' takes X days, weeks, months or years.
Interesting story, though. What's up next for the kids? Brain surgery?
