Swelling of the lower eyelids of babies is considered to be caused by prolonged crying, allergic conjunctivitis and renal insufficiency. 1. Prolonged crying: If the baby cries for a long time and rubs his eyes, the child may have swollen lower eyelids. 2. Allergic conjunctivitis: allergic baby is prone to allergic diseases, when encountered with air pollution or pollen particles in the air can easily cause eye allergies, which can cause the baby’s lower eyelid swelling, but also eye itching and other uncomfortable symptoms. 3. Renal insufficiency: children with renal disease due to renal insufficiency, the kidney drainage function can be reduced, resulting in sodium and water retention, which leads to the baby’s lower eyelid swelling performance. It is recommended that children with swollen eyelids consult a doctor in time to assess their condition and follow the doctor’s instructions for treatment.