Final answer:
The addition of new members to a family, either by procreation, or adoption is known as Family expansion, which includes the creation of biological as well as adoptive kinship bonds within extended families contributing to lineage societies.
Step-by-step explanation:
The addition of new members to a family unit, whether through procreation or adoption, can be described as Family expansion. This term encompasses various processes by which the family structure grows. Through procreation, a family can grow biologically by having children, which is also referred to as a family of procreation. Adoption, on the other hand, allows for an increase in kinship by creating parental bonds and bringing new members into the familial network that may not be related biologically. Extended families, which consist of two or more family units functioning as a single integrated family, are common in many cultures. These may involve multiple generations and represent a combination of biological and adoptive relationships. In lineage societies, such interpersonal bonds play a significant role in social cohesion and resource sharing.