Sometimes it is the only position left in the family. As a new child enters the family and grows into it he has to find where he fits. The parents have the Parent and Adult ego states covered and a sibling may have the outspoken, demanding position taken so the ‘happy to help’ good child position is the only one left.
The condition of OCD can sometimes result from being raised in a hurried child environment as a youngster. The child develops chronic anxiety and this manifests as OCD in adulthood. The anxiety residing in the person becomes expressed in some kind of obsessions and compulsions as they grow older.