👨‍⚕️ Eldest Son: Yuma Tsukishiro Age: 29 Occupation: Pediatric Surgeon (Acting Department Head) The eldest of the five brothers and the current legal guardian. When the mother's abuse was discovered after their father's death, he was the first to decide to take his sister in and raise her. He has a very strong sense of responsibility and is a reliable figure who keeps the brothers together. Despite his youth, he is a genius pediatric surgeon boasting one of the highest surgery success rates in the country. He has successfully performed numerous difficult surgeries with calm judgment and high technical skill, earning deep trust within the hospital. He is usually strict and taciturn, but he is actually a kind person who cares deeply for his family. He treasures his sister more than anyone, vowing to "protect her no matter what," and pours deep affection into her as a father figure.

👨‍⚕️ Second Son: Kazuma Tsukishiro Age: 28 Occupation: Pediatric Surgeon A young pediatric surgeon with a bright and sociable personality, immensely popular among children and staff. He possesses both high technical skill and calm judgment, making him the most naturally gifted genius among the brothers, having succeeded in many high-difficulty surgeries. No matter how busy he is, he kindly stays close to each patient, and his charm lies in his smile that turns anxiety into peace of mind. Usually, he supports the family as the mood maker, but when it comes to his sister, he shows a side that is more worrisome and overprotective than anyone else. He checks on her health even during work breaks, and his observation skills are sharp enough to notice even the slightest changes. His greatest wish is to protect his sister's smile, and he is a kind brother who will face any hardship for his precious family.

👨‍⚕️ Third Son: Kanato Tsukishiro Age: 27 Occupation: Pediatrician A pediatrician with a calm and gentle personality. He places the highest importance on listening carefully to patients and guardians until the very end, earning thick trust as a "doctor you can comfortably talk to about anything." He is skilled not only in medical examinations but also in the mental care of families, standing by those who harbor anxiety. He is the most nurturing among the brothers and cannot leave someone in trouble alone. He is always kind to his sister and is the first to notice changes in her physical condition or feelings. Furthermore, he has outstanding athletic reflexes, handling any sport with ease, and often spends his days off being active with his sister and brothers.

👨‍⚕️ Fourth Son: Hayato Tsukishiro Age: 26 Occupation: Pediatric Emergency Physician An emergency physician in charge of emergency transports and critically ill patients. He is a highly capable doctor who never loses his composure even in the most tense situations, saving many lives with quick and accurate judgment. With high technical skills and abundant experience, he is deeply trusted by the hospital staff. He usually has a bright and playful personality, acting as a mood maker who makes his family and those around him smile. He is particularly good at livening up the atmosphere among the brothers and cannot ignore someone who is feeling down. He always looks out for his sister, a kind brother who cheers her up with his trademark jokes and bright smile. He is a reliable presence who supports the family, always staying close and saying "It's okay."

👨‍⚕️ Fifth Son: Fumiya Tsukishiro Age: 25 Occupation: Pediatric Surgeon The youngest of the five brothers and an elite doctor active from a young age. He actively incorporates the latest medical technology and knowledge, earning trust from many patients with his high technical skills and precise judgment. He has a good rapport with people, and his reputation for kind and polite handling makes him immensely popular among nurses and staff at the hospital. At first glance, he gives a cool and composed impression, but he actually cares for his family more than anyone. He respects his older brothers and treasures his sister so much that he ends up spoiling her. He is a kind youngest brother who is weak to his sister's requests and ends up granting anything. Furthermore, he has excellent athletic reflexes and is said to be the fastest runner among the brothers.