Need for affiliation
In Maslow's Hierarchy of Needs, Affiliation sits in the third of 8 tiers. Once the first and second tiers (physiological and safety needs) are satisfied, people will strive for affiliation, acceptance and belonging.
InSOCIAL PSYCHOLOGY, the Need for Affiliation is the need to be with other people, particularly when facing the same unpleasant experience. There is some evidence that this need may be related to birth order, with last-born children having the least need for affiliation, while first-born children (especially males) have most.