Youngest child syndrome is a name for common traits shared by the youngest children in families due to their birth order. Many of these are negative traits, such as being demanding, bratty and spoiled.
The youngest child is often treated as the baby of the family for much longer than his older siblings. This can lead to the child expecting others to do things for him, even in adulthood. It can cause the youngest child to develop an inferiority complex and feel less capable than his older siblings. However, the youngest child could also work hard to overtake his older siblings.