Pink eye, or conjunctivitis, is an inflammation of the thin, clear covering of the white of the eye and inside of the eyelids. Anything that triggers inflammation will cause these conjunctival blood vessels to dilate and appear pink or red. Rebecca Kurzon, MD, an ophthalmologist at AdventHealth, says its often difficult to tell the difference between infectious causes and non-infectious causes. Call your doctor if your child has a pink eye and discharge and especially if he or she has eye pain as that may be a sign there is something more serious going on, she cautions.