So you are saying O Sr. left a family he hadn’t been with? How could he manage that? You can’t leave something you aren’t a part of. Surely I don’t have to explain these basics over & over & over...do I?
You show a lack of imagination that belies your screen name. I separated with (and eventually divorced) my son's mother and we both moved to new houses, but I continued to live in the same town and had regular contact with my son. He would not have said that I "left the family." But if I moved thousands of miles away and ceased to have contact except for phone calls and letters--and we don't know if Obama Sr. kept up contact even that much--then my son might say I left the family. You don't have to live together to be part of the family, in a child's mind.