An interesting post-canon tidbit given by Rowling revealed that Harry kept in touch with his long-time childhood tormenter (and cousin), Dudley Dursley, after the events of the final book. While it would have seemed implausible given only the first six books, a brief moment of reconciliation before their parting ways in Deathly Hallows gives this fact a bit of a pleasantly if slightly amusing sentimental vibe. Although, this isnt to say that they became very close friends at all: Rowling said that they were on Christmas terms, and would very occasionally have family get-togethers, in which Harry and Dudley would sit in stiff silence while their children would play together sounds like even Mr. Potter couldnt vanquish the abject evil that is the awkwardness of a family reunion.