Effie Wilcox is a local gossip and friends with Grandma Dowdel.
When Mary Alice and Joey are telling Grandma Dowdel about gossip they've heard, they say they heard it from a "humped-over lady with bucked teeth." Grandma recognizes this as Effie Wilcox, and she says was cross-eyed and even uglier as a girl than as an adult woman. She says that Effie is a gossip and that you should never trust an ugly woman because they have something against the world.
However, Grandma doesn't dislike Effie as much as it seems she does. Throughout the book, it's obvious that she feels some kind of affection for her. She even bargains with the banker to get Effie's house back free and clear after it's taken away from her. She goes with her grandchildren to the depot the day they leave, but it's not to say goodbye to them. She goes to welcome Effie home. The kids look back and wave, but Grandma is already absorbed in whatever Effie is saying to her.