In "In a Field of Stray Caterpillars," how does Alice end up at Beth's house?

One of the errands that David and Fellis are supposed to run is to pick up medications for both Beth and Alice. When Fellis drops off his aunt's blood pressure medication, however, he accidentally leaves his mother's Adderall instead, and after Alice takes one of these pills, she panics and calls Beth for help. Beth goes to pick her up and brings Alice back to her house so that she can give her something to relax her and calm her down.