Let's examine the evidence
Obviously, Niall Horan is a fan of eating. The Teenage Mutant Ninja Turtles have been known to put away more than a few pizzas in their time, and also have a knack for bouncing around with more energy than Caroline Flack in the M&S boys' department.
So Niall is clearly their brother-from-another-mother (and they totally count as superheroes).
Just Louis left now, click next to see what's in store for him...