Just finished reading Matt Birkbeck's "A Beautiful Child". It was written very well. It was very sad to read all of the pain and suffering she endured.
As to any possible theories as to the true identity of "Sharon Marshall" I gained from reading the book, I suppose they basically remain the same as I've posted in an earlier post.
I think Franklin Floyd either took this young girl from A.) a family member, parent(s) that didn't care for her and never reported her as missing, possibly because "Sharon" was born and raised at home, without a SSN and/or record of her even existing. Parent(s) who were drug addicts, destitute, homeless, or mentally ill just as an example. Not saying all parents like this would treat their kids that way, for the record. Maybe her parent(s) didn't live very long after she was taken- hence no official report of her missing? B.) a family that had legal/law enforcement problems that might bring unwanted attention to themselves by LE. Probation, parole, theft-ring activity, religious sects, terrorism networks (Vietnam era), or underground child exploitation/black market selling of children, that the parent(s) might have been involved with or problems in the past w/LE, etc. C.) Floyd may have possibly taken this child during a house fire and/or natural disaster or accident, where next of kin were all presumed dead, therefore negating inquiries. D.) Did Floyd have a passport? Knowing how slick he was with his paperwork, I'll assume he did. If so, where did he travel out of the country to? Canada, even Alaska although it's a U.S. state. I mention this because many of these areas the land is remote and rural. Some people live simply w/out the need for the bustle of the city and do just fine.
I just find it hard to believe that after all these years, and having "Sharon's" DNA available for comparison, that some link would not have been matched unless someone didn't want to report her as missing for unspecified reasons. Or couldn't report her as missing. Any thoughts??? Sorry for the long post, btw!