Because of Winn-Dixie
Nobody's perfect. That's Gloria's consistent message to Opal. Her own mistakes have taught her that.
And Opal listens to her more than, well, anybody else. Why? Because Gloria truly listens to her.
So when Gloria advises Opal to avoid passing judgment on Otis, shows her a different way to look at the Dewberrys ("I think they are just trying to make friends with you in a roundabout way"), and tells her "that the whole world has an aching heart" (20.10), Opal gets it. These little tidbits grow inside of Opal's heart, just like the wait-and-see Seed. (See "Symbols" for more about that one.)
Thank you, Mentor Dump.
Miss Franny Block
Miss Franny doesn't give advice; she tells stories. Her most important story is about her great-grandfather, Littmus W. Block, who created the sweet and sad Littmus Lozenges (Head on over to "Symbols" for a more detailed explanation).
If not for her story and candy, Opal would never have understood why Amanda was so rude all the time, and she'd have missed out on a great friend.
But Miss Franny's influence is even bigger than that. Eating those candies and watching her friends eat them teaches Opal about sorrow and sweetness—how life is a mixed up bag of both.
Thank you, Guide Block.