Heartwarming / The Way, Way Back

• When Duncan gets visibly uncomfortable at how his mother is acting at the barbecue, Susanna, knowing he won't go with her if she asks directly, instead asks her brother if he wants to go chase ghost crabs (as he was playing under a table the whole time) and asks Duncan if he wants to come too. Framing it this way made it more likely for him to accept.
• In a minor sense, when Duncan is forced to break up the dancers at the water park, though he's awkward and shy as ever, the kids don't make fun of him and instead teach him a bunch of moves and nicknaming him "Pop 'n' Lock." This is one of the first times Duncan feels accepted in the entire film that has nothing to do with Owen or Susanna
• Duncan's friendship with Roddy and especially Owen because both of them treat him like a younger brother and even when they're ribbing him it's clear that he's having fun, too.
• Owen giving Duncan the approval and reassurance that no one else has and telling him he is not below average as Trent says.
• Owen telling Peter how much he likes his crooked eye and telling him about all the jokes he could make with it, especially considering how his mother forces him to cover it up.
• Owen stepping in front of Duncan when he meets Trent and making clear to Trent that he would love nothing more than an excuse to beat the shit out of him.
• In contrast, when Owen meets Pam, he tells her that Duncan is "One hell of a kid".
• Owen and Caitlin's relationship. When Caitlin gets fed up with Owen's behavior and begins to hint of leaving, he sobers up immediately, tones down his Manchild tendencies, and sincerely apologizes to her. It's clear that beneath their frivolous behavior that they both care for each other.