One-and-a-half-year-old boy Tong Tong, looking tiger head, people love. But Tong Tong’s mother has always had a problem, because since childhood, no matter where they go, people who see Tong Tong say: “This child is really good-looking, but unfortunately is a ‘cross-eyed’.” “Is my child ‘cross-eyed’?” With this question, Tong Tong’s mother brought Tong Tong to the hospital. After a careful examination, the doctor told the mother that her child was not “cross-eyed”. “But why do people who see Tong Tong say he is ‘cross-eyed’?” The mother questioned. The child has pseudo-internal strabismus, which is caused by canthus. The inner canthus is a vertical half-moon skin fold that covers the inner canthus, usually symmetrical in both eyes, mostly seen in childhood, especially in those with flat nasal bridges, because the redundant skin covers the inner canthus and part of the nasal bulbar conjunctiva (i.e., the inner “white” part of the eye), it appears that both sides of the cornea (black eye) have the feeling of leaning inward, thus giving the appearance of This gives the illusion of “crossed eyes”. The child inherited his mother’s flat nose, giving the illusion of “cross-eyed” eyes. Mild canthus does not need to be treated, as children grow older, the nasal bones develop and the eyes develop, the canthus will mostly disappear naturally; if it is still obvious in adulthood, cosmetic surgery is feasible. After hearing the doctor’s words, the mother’s heart finally dropped.