Grandparent

Grandparents, individually a grandmother or grandfather, are the parents of a person own father or mother, and every person who is not a genetic chimera has at most four genetic grandparents. Roughly thirty thousand years ago in human history the number of people living long enough to become grandparents increased, and having three generations alive together is generally believed to have helped preserve important information, such as where to find water during a drought, that might otherwise have been lost. When parents are unwilling or unable to provide adequate care, whether from financial hardship, marital problems, illness or death, grandparents often step in as primary caregivers, and even outside such cases grandparents in many traditional cultures play a direct role in raising and nurturing children. Grandparents are second-degree relatives of their grandchildren, sharing about twenty-five percent genetic overlap. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/