For the 21 years of our oldest daughters’ life, we have been contemplating the issue of our kids’ relationship with their grandparents. You see, our kids have grown up far away from their grandparents most of their life, but their relationships with one side of the family is stronger that with the other side.

To my surprise, the relationship to grandparents has nothing to do with how nice the grandparents are or what culture they are from, how nice you are, how nice your kids are or where you choose to live around the world. It is linked more closely to evolution – that survival mechanism of humanity to keep the dynasty and strengthen it. Grandparents invest in the grandchildren they are convinced are theirs.

In 1998, a researcher named DeKay came up with a theory to explain findings from researches conducted two years previously (Euler & Weitzel, 1996 and Boon & Brassoni, 1996) who claimed that grandmothers on the mother’s side invested in their grandkids the most. DeKay came up with a theory linking the relationship between grandparents and their grandchildren to certainty. His theory was that grandparents invest in the grandchildren they are certain are their offspring. In other words, the grandparent who has less doubt of being genetically related to the child and therefore to the grandchild, is more likely to invest in this relationship to support his or her “breed”.

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