Feeding behaviours and oral motor development are essential for adequate nutrition and management of medical conditions, but ethical and practical challenges limit direct tests, especially in infants. This study introduces BabyBot, a robot mimicking the oral-brain system with sensory-motor control pathways. Equipped with soft robotic tongue,sensorized oral cavity, and neural circuits, the robot can perform complicated tongue movements, replicate and modulate feeding-reflex programs. BabyBot is designed in modularity to simulate developmental stages from birth to six months. The robot’s performance and food intake efficiency are validated to match human physiology, and it can effectively handle liquid and semi-solid foods. Furthermore, BabyBot can demonstrate abnormal situations, including immature sucking in preterms, gag reflex to inappropriate feeding, and inadequate movements. Our work not only provides an in vitro simulator that simulates infant physiological behaviours and development, but also highlights the potential of soft robotics in pediatric care, biology evolution, and biomedical engineering.