Have fun in the sun with this adorable sunlight-activated color-changing t-shirt for kids. A white kids t-shirt with the "Let Your Heart Grow" message in black with a heart flower design. When exposed to sunlight, this youth tee brightens and transforms from basic black line art to vibrant, sunny colors. A great gift and fun tshirt to wear, for girls or boys, or to teach kids about the concept of photosynthesis. Machine wash cold with like colors and tumble dry low. 100% cotton.