What eventually happened to Frank? How does David feel about it?

When he realizes that he is going to be turned in for his crimes, Frank kills himself by slitting his own wrists and letting himself bleed to death. David takes his time walking up the stairs because he’s trying to conceal his satisfaction. He naively believes that his uncle’s suicide has solved all their problems and life will return to normal, almost as if none of this had happened. As he climbs the stairs, David feels gratitude and love for his uncle.