Being a Harry Potter fan, I remember how much I hated the family Harry stayed with, The Dursleys. Not only were his aunt & uncle horrible, his cousin Dudley was also the worst brother ever. A big bully, he was super spoiled by his parents, Vernon & Petunia, and every time he tortured poor Harry, I felt like kicking him hard.
But then, everyone grew up. Harry had much more serious issues to handle (like Voldemort) than Dudley. Though the two were always at loggerheads.
Eventually we all warmed up a little to Dudley, who in his own way had changed a little bit. Harry puts it best: "He only said he didn't think Harry was a waste of space! But coming from Dudley that's like I love you."