Wendy tells Garrett and Carolyn that she's going back to Josh and Louie, and they don't try to argue with her decision at all.
After saying her goodbyes to all her friends, like Henry and Violet, she takes the train all the way across the country.
Before she goes, though, Wendy opens the box of gifts from her mother and sees all the little trinkets and inside jokes within. There's also a plane ticket to California—her mother meant to let her go see her father after all.
On the long train ride, Wendy has conversations in her head with her mom where she tells her about visiting California. She wishes her mom could come back.
Wendy hasn't told Josh that she's coming, so when she finally gets to New York, she goes to their apartment and lets herself in. She sets her things down in the room and peruses her parents' room.
She then decides to walk to Louie's school and pick him up. He looks up from where he's sitting and tells her that he dreamed that she came home.
As they walk out of the classroom together, she tells him that she's so lucky to have him for her brother. And he tells her that he finally learned how to skip.