Johanna Hurwitz invites readers into the world of the funny, lovable Kelly twins, who are truly two of a kind. Second-graders Arlene and Ilene Kelly are twins—identical twins to be exact—and they love being a pair. They love to dress alike, they have identical pet ferrets, and they do everything together. But being a twin is not always easy. When a set of triplets comes to school, Arlene and Ilene wonder whether triplets are more special than twins. At Halloween, on different streets in identical witch costumes, some neighbors think that the girls are one person trying to get extra candy. And when Arlene gets sick and has to visit the hospital, the twins each find out what it’s like to be one instead of two. But whether they’re together or apart, Arlene and Ilene know they’re lucky to have each other.

What’s the same about identical twins—and what’s different? Sleepovers, poetry projects, and new haircuts are in play as seven-year-old Arlene and Ilene start coming into their own. Arlene and Ilene love so many things about being identical twins. They like sharing a room, sharing friends, and wearing matching outfits. But they’re in different classes at school, and one twin has a scar that the other one doesn’t. One morning, their friends Monty and Joey point out a new difference that takes the sisters by surprise and gets them if they are identical twins, why are there differences between them at all? Their tongues must be the same, so why do they like different kinds of ice cream? Why does Arlene wear pink nail polish while Ilene thinks it’s silly? Why is Ilene sleeping soundly when Arlene is awake, wondering how she can be sure that she is Arlene, not Ilene? Revisit the funny, lovable characters from The Two and Only Kelly Twins and take a peek at the wonders—and puzzles—of being an identical twin.