Each year, over 25 million children are hospitalized in the United States. Separated from their parents during procedures and overnight stays, many experience acute separation anxiety — fear, disorientation, and a profound loss of agency that can slow recovery and leave lasting psychological impact. Yet the designed environment of the pediatric ward has changed little in decades. Lumina Echo is a response to that silence. The device projects layered light patterns — forests, animals, constellations drawn from children's visual language — across the walls of a hospital room, turning a clinical space into something inhabited and personal. A rotating cylindrical shell with hand-cut imagery casts shifting shadows as children touch and turn it, while embedded sound responses make the environment feel alive and attentive. Developed through eight months of research with children, caregivers, and medical staff, and validated across three rounds of hospital-based interaction testing, Lumina Echo integrates physical craft, interaction design, and electronic engineering into a single coherent object. It is not a medical device. It does not treat the illness. It simply ensures that while a child waits — in an unfamiliar room, under unfamiliar light — they are not waiting alone.