Sarah is a 37-year-old vice president of human resources at Berkeley Consulting, an international firm in Boston. She maintains an intensely fast-paced lifestyle, working 80-hour weeks while trying to remain an active parent to her three children. A severe car accident leaves her with a traumatic brain injury and a condition called Left Neglect, forcing her to halt her career and rely entirely on others for her daily survival.

Bob is Sarah's husband, who works demanding hours at an information technology start-up company. Like Sarah, he is highly driven and tries to balance his professional ambitions with his responsibilities as a father. Following Sarah's accident, he suddenly finds himself entirely in charge of the household and his wife's medical decisions.

Helen is Sarah's mother, who lives a quiet, solitary life on Cape Cod. She has been emotionally distant from Sarah since a family tragedy years ago, causing a deep rift between them. Following Sarah's accident, Helen leaves her comfort zone to help care for her grandchildren and assist in her daughter's physical recovery.

Charlie is Sarah and Bob's seven-year-old son, currently in first grade at Welmont Elementary. He is bright and active but has significant difficulty focusing in school and following multi-step directions at home. His behavioral differences often set him apart from his peers, prompting formal evaluations.

Lucy is Sarah and Bob's five-year-old daughter. A lively kindergartner and natural rule-follower, she relies heavily on her mother's attention and adapts quickly to the shifting dynamics in her household.

Linus is Sarah and Bob's nine-month-old baby. He spends his days with the family nanny or at daycare while his parents work long hours. Following Sarah's accident, his care shifts primarily to his grandmother.

Heidi is an occupational therapist and a fellow parent at the school Sarah's children attend. She becomes a vital part of Sarah's rehabilitation team at the Baldwin center, offering both professional guidance and genuine friendship during the difficult recovery process.

Richard is Sarah's boss at Berkeley Consulting. He relies heavily on Sarah's high-level recruitment and management skills, keeping the pressure high in their fast-paced corporate environment and eagerly anticipating her return to the office.

Jessica is Sarah's assistant at Berkeley Consulting. She helps manage Sarah's incredibly tight schedule and heavy workload, appearing shocked by the severity of Sarah's condition when visiting the rehabilitation center.

Ms. Gavin is Charlie's first-grade teacher at Welmont Elementary. She expresses sincere concern over Charlie's lack of focus and ability to complete tasks in the classroom, guiding his parents toward formal evaluation.

Nate is Sarah's younger brother who died in a drowning accident when they were children. His death deeply impacted the family dynamic and caused a long-standing emotional rift between Sarah and her mother.

Martha is a physical therapist at the Baldwin Rehabilitation Center. She works to help Sarah regain mobility and retrain her brain to recognize the existence of her left side.

Dr. Kwon is Sarah's neurologist. He officially diagnoses her with Left Neglect and guides her early recovery, explaining the complex mechanics of her brain injury to her family.

Abby is the Nickerson family's nanny. She cares for the young children during the day and helps shuttle them to extracurricular activities until leaving for an internship.

Mike is a staffer at an adaptive sports program in Vermont. He teaches Sarah how to use a modified snowboard, helping her find a new, accessible way to enjoy winter sports.