2.) Relationships over the lifespan are evolved by the child as they feel connections and trusts towards others. When the child feels comfortable with others they allow deeper relationships to develop and there are stronger ties to others. If these connections do not start soon in the child's life, then the child may not ever have developed an adequate bond with their parents, and may never have deep, meaningful relationships with their peers.
3.) Theories of development all differ slightly from each other. Some of these theories are centered around the child's growing relationships with others as a key to development of the child as an individual, such as the psychosocial theory and the social identity theory do. Other theories such as the moral development theory are based upon the child's own inborn thoughts and feelings guiding their relationships with others, based on their sharing characteristics with others.
4.) All cultures value different relationships as more or less important. These values are determined by the cultural settings as well as the cultural beliefs. Some societies value independence and strength for people, while others have strong group values and beliefs. Therefore some cultures have a very strong social behavioral structure based on the culture as a whole, while other cultures do not.
5.) Parent-child relationships are very different from culture to culture. In some cultures children are raised by their parents, knowing that one day it would be expected that they would return the favor when their parents were older. In other cultures children are not expected to care for their elderly parents when they are adults which seems to be the way general American culture is. There are several foreign cultures which expect the children to care for the parents, and those countries have very few elderly care facilities, there are hundreds in the United States.