Fifty-Four Things Wrong with Gwendolyn Rogers by Caela Carter

From the critically acclaimed author of the ALA Notable and Charlotte Huck Honor Book Forever, or a Long, Long Time comes a moving own-voices story that shines a light on how one girl's learning differences are neither right nor wrong...just perfectly individual. For fans of Alyson Gerber, Cammie McGovern, and Kathryn Erskine.
No one can figure out what Gwendolyn Rogers's problem is—not her mom, or her teachers, or any of the many therapists she's seen. But Gwendolyn knows she doesn't have just one thing wrong with her: she has fifty-four.
At least, according to a confidential school report (that she read because she is #16. Sneaky, not to mention #13. Impulsive). So Gwendolyn needs a plan, because if she doesn't get these fifty-four things under control, she's not going to be able to go to horse camp this summer with her half-brother, Tyler.
But Tyler can't help her because there's only one thing "wrong" with him: ADHD.
And her best friend Hettie can't help her because there's nothing wrong with Hettie. She's perfect.
So Gwendolyn is hopeless until she remembers the one thing that helped her mother when her own life was out of control. Or actually, the twelve things. Can these Twelve Steps that cured her mother somehow cure Gwendolyn too?