Double eyelids are dominant genes, and dominant genes are more likely to be expressed in appearance because of their own characteristics, while the expression of recessive genes is generally not obvious. Alleles can be divided into dominant and recessive genes in terms of expression, and in chromosome pairing, regardless of how the chromosomes are paired, as long as the genes include dominant genes, they will express their own traits, such as double eyelids. This is because when the sperm and egg unite to form a fertilized egg, the dominant or recessive genes of both parents are combined together, but not simply mixed equally, but recombined in a different way on this gene, and therefore appear differently. There is a relationship between whether both parents have double eyelids and single eyelids and whether the child has double eyelids. If both parents have double eyelids, the probability of the child being double eyelid is about 75% and the child will also have some probability of being monocular. If only one parent has double eyelids, the probability of the child being double-eyed also decreases. However, if both parents have monocular eyes, they will generally only produce children with monocular eyes. If you are not satisfied with the aesthetics of your eyes, you can use double eyelid stickers, but they are more troublesome and may also cause fat to accumulate under the eyes and give rise to triple eyelids. You can choose a regular hospital for medical aesthetic treatment in adulthood, through the buried thread method, suture ligation method, and incision method.