Jeffrey falls off a kitchen stool and his nose bleeds so severely that his mother rushes him to the emergency room.

Steven's mom tells him that Jeffrey has been diagnosed with leukemia and needs chemotherapy immediately.

Steven's parents reveal that his mom has quit her job so she can care for Jeffrey full time.

Jeffrey and his mom leave for the Children's Hospital in Philadelphia to begin cancer treatment.

Jeffrey and his mom return home, and Steven learns that Jeffrey has just over a 50% chance of survival.

Steven's mom picks him up from the eighth-grade dance because Jeffrey has developed a dangerous fever.

Steven gives Jeffrey the Matt Medic action figure and tells him it will keep him brave during treatment.

Steven breaks down crying in a meeting with all his teachers and finally reveals that Jeffrey has cancer.

Steven discovers his dad alone in the kitchen, crying over a pile of medical bills totaling over $27,000.

Steven turns a sick Renee away from the front door to protect Jeffrey from being exposed to germs.

Mrs. Galley advises Steven to stop focusing on things he cannot change and work on things he can.

Steven shaves his own head to make Jeffrey feel less alone after Jeffrey is teased at school for being bald.

Annette and Renee devise a plan to transform the All-City spring concert into a fundraiser for the Alper family.

Steven meets Samantha at the Children's Hospital, and she asks him to promise to stay with Jeffrey no matter what.

Jeffrey achieves remission and shouts that he loves Steven at the eighth-grade graduation ceremony.

Jeffrey's unexpected leukemia diagnosis tears apart the Alper family's normal life and forces Steven to confront the real possibility of losing his little brother. While his parents struggle with the financial and emotional toll, Steven hides from reality, neglects his schoolwork, and refuses to discuss the illness with anyone. A pivotal meeting with his teachers forces him to open up, and school counselor Mrs. Galley's advice helps him channel his helplessness into meaningful action. Steven begins shaving his head, turning the school concert into a fundraiser, and ultimately choosing Jeffrey over his own ambitions. A promise made to a dying girl at the hospital cements his transformation when he walks away from his biggest performance to be at his brother's side. By graduation, Jeffrey is in remission and Steven has grown from a self-centered teenager into a young man who puts family first.

The core story of Jeffrey's cancer and Steven's transformation.

Jeffrey uses Steven's signed drumsticks to stir a pot of random ingredients he calls 'Dangerous Pie.'

Jeffrey embarrasses Steven in front of his crush Renee after the All-City Jazz Band concert.

Mr. Watras asks Steven to play the conga part in Dizzy Gillespie's 'Cubana Be Cubana Bop' for the spring concert.

Annette asks Steven if Jeffrey is okay; Steven apologizes for angrily snapping at her on the bus.

Jeffrey returns home from Philadelphia with two black eyes and a badly swollen nose caused by leukemia bruising.

Jeffrey gives Steven a box of orange Tic Tacs as a gift, then immediately vomits on Steven's sneakers.

Steven tries to bargain with God, promising to give up sweets and impure thoughts to keep Jeffrey alive.

The ER doctor announces that Jeffrey must be transported by ambulance to the hospital in Philadelphia.

Steven is sent to his grandparents' house after catching the flu so he won't expose Jeffrey to germs.

Jeffrey receives blood transfusions during a hospital visit, and Steven's mom warns Steven to keep Jeffrey away from sick people.

Steven accuses his dad of being irresponsible; his dad breaks down and admits he has failed his family.

Renee apologizes to Steven on the bus after he jokes about failing math to break the tension between them.

Annette arrives at All-City Band rehearsal with her arm in a cast and announces she cannot play in the concert.

Steven's dad surprises the band with a speech thanking them and admitting his family needs him more than extra money.

Annette wins the first-ever Human Service Award at the eighth-grade graduation ceremony and receives a standing ovation.

Before Jeffrey's illness even begins, small moments like the Dangerous Pie incident and a concert humiliation establish the complicated love-and-annoyance dynamic between the brothers. As Jeffrey's treatments progress, secondary events pile pressure on Steven from every direction, including a vomit-covered reunion, a cancelled tutoring session, and a flu-forced exile to his grandparents' house. Relationships with Annette and Renee evolve through small but meaningful confrontations, including a makeup conversation on the bus and Annette arriving at rehearsal with a broken arm. Steven's dad, who had all but disappeared emotionally, finally cracks in a fierce argument that begins to rebuild their bond. The concert fundraiser crescendos with the dad making a heartfelt speech to the band, acknowledging that his family needs him more than extra money. The story closes with a touching final letter from Samantha passed on through a package of returned drumsticks.

The secondary moments that shaped Steven's difficult year.

Steven's first reaction to learning Jeffrey has leukemia is shameful relief that he won't get in trouble.

When told he must go to Philadelphia for treatment, Jeffrey's only question is whether Steven will come too.

Steven learns that his dad has been hiding Jeffrey's worsening medical updates from Philadelphia for an entire week.

Steven watches Annette playing piano through a doorway and is surprised to find her beautiful for the first time.

Steven nearly faints while holding Jeffrey's hand as a large needle is inserted into the Port-a-Cath in Jeffrey's chest.

Renee reveals on the bus that she — not Annette — was the one who told Miss Palma about Jeffrey's cancer.

Jeffrey sends his Matt Medic action figure to Steven while Steven is sick at his grandparents' house.

Steven begins having a recurring nightmare in which he accidentally causes Jeffrey to sink into the ground.

Mr. Stoll refuses Steven's prized Special Sticks as payment and offers to make Steven's drum lessons free instead.

A classmate teases Jeffrey for being bald, and Jeffrey confesses to Steven he didn't want Steven to know.

Steven's mom falls ill with a stomach bug, forcing Steven and his dad to take Jeffrey to Philadelphia without her.

Jeffrey realizes he forgot Matt Medic before the Philadelphia trip and asks Steven to take Matt Medic's place.

Steven gives Samantha his favorite drumsticks as an early birthday present and promises to give her drum lessons.

Steven's mom reveals backstage at the concert that she knows about the free drum lessons and hugs Steven.

Steven goes to find Samantha at the hospital and learns from a nurse that she died the morning before.

Even before Steven processes his grief, a shameful first reaction to Jeffrey's diagnosis reveals how far he has to grow as a person. Small revelations shift his understanding of the people around him — his dad hiding medical news from Philadelphia, and Renee turning out to be the one who told Miss Palma about Jeffrey. Watching Annette play piano alone is the quiet moment Steven first sees her as more than just a friend, planting the seed of a real relationship. As Jeffrey's illness deepens, each turning point — a recurring nightmare, Stoll's unexpected generosity, Jeffrey forgetting Matt Medic — pushes Steven further toward maturity. A birthday gift of drumsticks to Samantha and a backstage hug from his mother crystallize just how much Steven has changed without him realizing it. The discovery that Samantha has died alone, without her sister by her side, makes every choice Steven made that year feel irreplaceable.