The redness of the lower eyelids of children may be related to inflammatory stimulation, allergic reactions, mosquito bites and other reasons. 1. Inflammatory stimulation: If a child suffers from contact blepharitis, blepharitis and other inflammatory diseases, it will stimulate the skin of the eyes, resulting in blood vessel dilation and congestion, and the tissue fluid exudes and flows to the lower eyelid, which will make the child’s lower eyelid red. 2. Allergic reaction: when the skin of the eyes comes into contact with allergic substances, such as willow flakes, dust mites and animal dander, an abnormal immune response will be produced, which will lead to redness of the lower eyelids of children. 3. Mosquito bites: If a mosquito bites a child’s lower eyelid, the toxin enters the skin and the skin becomes allergic to the mosquito’s venom, resulting in redness of the child’s lower eyelid. It is recommended that the patient go to the pediatrician in time to identify the cause of the disease and then correctly treated.