No. People of different age groups can have codependent personalities. In many cases, codependency can be traced back to childhood. It develops when a person is raised by overprotective or under protective parents.
Whether the codependent person is a child or an adult, they exhibit the same behavioral patterns. They continuously look for ways to help people around them, even when help is not required. The effect of appreciation that they receive for their efforts is short-lived and they start feeling inadequate again.