Cherry reflects on the daily, trivial exchanges that sustain a person when they live with someone they love, and how losing Ned forced her to rebuild a structure for her life. She established a weekly phone call with her childhood friend Ivy—Sunday evening in America, Monday morning in Australia—during which they reminisce about childhood memories, reconnecting Cherry with the carefree girl she once was.

Cherry also began attending Tuesday aqua aerobics with Mira, who generously shares her family with Cherry. When Mira's granddaughter Bridie whispered that she was "too dumb for math," Cherry was heartbroken and determined to help. She went through Ned's collection of over forty small hardback notebooks, which he had kept in a shoebox. In them she discovered the recurring acronym "OGT"—One Good Thing—a gratitude practice Ned had started during a dark period after his divorce and continued for years. Many of his entries were about Cherry: her eyes, her blue dress, her legs, conversations about memories and mathematics, singing in the car together.

One entry triggered a vivid memory of a Sunday morning conversation in bed about mathematical Platonism—the idea that mathematical truths are discovered rather than invented, suggesting reality extends beyond the physical world. Cherry and Ned had wondered whether her mother's psychic sense might be analogous to math as a sense, potentially bridging Cherry's love of mathematics and her mother's spirituality. The philosophical reverie was interrupted when Ned remembered an Aldi sale on camp chairs, and they rushed out, arguing about air vents in the car.

Cherry now reads one of Ned's notebooks each night before sleep, sometimes traveling back through memories to feel she is with him again. She recalls that her mother, during her final reading, told Cherry to "look for the notebooks." Weeks after finding them, Cherry dreamed of her mother dancing in their old kitchen, singing "Told you so!" Cherry acknowledged her mother was right about the notebooks but also felt bitter that her mother hadn't warned her about Ned's heart. Their relationship, even beyond death, remains somewhat fractious.

The notebooks also provided Cherry with lesson-plan ideas for tutoring Bridie in math every Wednesday. Though Cherry admits she is no natural teacher, she is improving alongside Bridie. One day Bridie said she loved Wednesdays, and Cherry realized Bridie meant she loved coming to Cherry's house. Cherry then told Bridie about her mother's long-ago fortune: that one day a little girl whose name began with B would arrive on a plane just when Cherry needed her most. Bridie slowly realized Cherry meant her, and Cherry confirmed it.