Do not confuse social relationships with biological relationship. A person can have only one biological Mother and Father, that is what is going to be traced if you do DNA testing. Social pressures will not change that fact.
While social relationships are important, there are many siblings, adopted parents, friends, relatives, and playmates. It will be impossible to track their influence on a person.
I have a connection to Cecil B DeMille. The minister who married my great grand parents, had a son who wrote the Robe, which DeMill made in to a movie. It is interesting but meaningless.