This statement is actually a folk saying. It is said that the songbird still holds the baby's gift for pregnant women with its long mouth, and the scar on the child is the hickey left by the songbird.

"Crane hickey" is medically called neonatal erythema, which has existed in children since birth. It generally refers to the pink patches on the baby's scalp, from the neck to the back or on the skin across the eyelids, or even any part of the body. Erythema neonatorum is basically distributed near the midline of the baby's body and will hardly be noticed at birth. About one third of babies can see "crane hickey" at birth. As the baby grows up, the blood vessels gradually contract and the skin becomes thicker, and it will disappear or decline when it is about one year old.