The best friends in Wilson's novel might be special in multiple ways. They could be from different backgrounds, yet find common ground in their values and dreams. Their relationship might be a source of growth for both of them. For example, one friend might be brave and encourage the other to step out of their comfort zone. They could also have a shared sense of humor that only they understand, which helps them get through tough times. And perhaps they are special because their friendship endures despite the many challenges and obstacles that the plot of the novel throws at them.
Since we don't know the exact Wilson's novel, it's hard to say. But generally, special best friends in a novel might have unique qualities like loyalty that goes beyond the ordinary, or they might have a shared past that no one else understands.
In a Wilson's novel, the best friends could be special because of their ability to communicate without words. They might have a telepathic - like connection that allows them to understand each other's thoughts and feelings in an instant. Maybe they have different personalities that complement each other perfectly. For instance, one is very outgoing and the other is more introverted, but together they make a great team. Also, they could be special because they are willing to sacrifice their own interests for the sake of the other. This selflessness is a key aspect of many great fictional friendships.