As far as I know, no one has ever found any direct proof of Lucy's maiden name or of the given names of her Cook and Roberson husbands. Lucy and her children appear to have moved into Tennessee around 1810 from a part of Jackson County Georgia that was originally part of Franklin County. The records for Franklin County in the late 1790s and early 1800s are fragmentary and very incomplete. Some early Roberson family researchers who have been through the existing records in Jackson County Georgia suggest that Lucy's maiden name may have been Phillips and that her second husband may have been a John Roberson. But this is conjecture with no proof. They were uncertain regarding whether her second husband died in Georgia or in Tennessee. Their research notes, which are very confusing, were published in a document called "The Rober(t)sons Have Arrived." I don't have a complete copy but it is apparently available from some libraries.