I believe the answer is: Inductive generalization
Inductive generalization refers to the type of thinking that believe something is universally true based on small sample.
Example of inductive generalization, all people in my family do not like Brand A of cereal. So, Brand A cereal is not well-liked by average family in my City.
The answer is mutuality among peers. In addition in the young adulthood, the responsibilities in this stage are centered in the order of the drive to found intimacy, connection, and significant peer relationships. The post persuasive and significant peer relationship is marriage, and this is also the relationship that trends toward the most depth and intimacy. As a result the resolution of the psycho-social crisis is attained by establishing intimacy (mutuality) between peers.