Barry Davis?
It is possible, but from what I have heard about Frank Marshall Davis’s wife, she had no problem with Frank doing whatever he wanted, but that excluded having children with other women. She had money.
If he did impregnate Stanley Ann, he would never admit to being the father. So Obozo is probably listed with father unknown.
In the beginning I put little credibility in the idea of FMD being the father. Now it is anyone’s guess.