I believe that Obama is really the son of Davis. I think that is why he was given so much time with Obama. On one site I’ve read, there are pictures, taken by Davis, of Obama’s mother at age 15 or 16 in the nude.
All the nude photos were proven beyond a shadow of a doubt to be someone other than Stanley Ann, and the photographer had no connection to Frank Marshall Davis. It is a made up theory, probably made up to distract from his real background, and to make those who doubt the official story look like kooks. There are several in depth threads about this.