I am researching Joseph Bartlett - suddenly he just exists in some research and others he is claimed to Robert and Mary Warren Bartlett - which is it?

Some say he is and others say he is not the son of the Robert Bartlett  and Mary Warren who came to this continent on the "Ann".  others can not say who the parents are of Joseph Bartlett married to Mary Wayt.  Here in Geni it says that he was married to Hannah Pope, then eventually to Mary Wayt.  How can the truth be uncovered?