There are several reasons for nosebleeds in the middle of the night in 2-year-old children: 1. The most common reason is that the air in the room is dry and the brittleness of the nasal mucosa increases, leading to rupture and bleeding of the nasal mucosa capillaries. 3, may be a blood system disease, should promptly go to the hospital inside the blood test to see if there is a decrease in the number of platelets; 4, a few is due to abnormal nasal development, nasal mucosa and blood vessel abnormalities will easily appear nosebleeds, should take the child to the Department of five organs for examination and treatment.