Were Lincoln and Ward Hill Lamon law "partners?"

[L Verge]

A few nights ago, I did a little searching online about this continuing discussion of Lincoln and Davis being half-brothers. First, I found that Samuel Davis, who is claimed to be Lincoln's "real" father, was born in 1756, so he would have been 28 when Nancy Hanks was even born and 53 when he seduced her. Possible, but...

I also found this:

Many have claimed relationship to Jefferson DAVIS through descent from sisters of his father, Samuel Emory DAVIS, yet no one has ever proven that Samuel Emory DAVIS had any sisters (or full brothers). Samuel Emory DAVIS did have two half brothers (viz., Isaac WILLIAMS and Daniel WILLIAMS), who were sons of his mother, Mary EMORY, by a former husband (identity unknown).
Many have claimed relationship to Jefferson DAVIS through descent from siblings of his grandfather, Evan DAVIS, Jr., yet of Evan Jr.'s five siblings, three have been proven not to have had any children (no children are named in their wills), and there is no evidence that the other two ever married or had children. To quote the leading authority on the genealogy of Jefferson DAVIS:

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"The outstanding characteristic of the Davis family seems to be that its members were as short lived as they were unprolific."

Only two of Jefferson DAVIS's siblings left descendants named DAVIS beyond one generation, namely, Samuel A. DAVIS (b. 1788/9) and Lucinda (DAVIS) DAVIS (b. 1797). So, the bottom line is that if your surname is DAVIS and you have traced your DAVIS ancestry back into the 1800's without connecting to the grandsons of Samuel or Lucinda, it's probably time to bury the family legend of being cousins to Jefferson DAVIS. You have a better chance of being blood-kin to Jefferson DAVIS if your surname is BRADFORD, MITCHELL, SMITH, or WHITE than you do if your name is DAVIS.

This comes from dgmweb.net/JeffDavisHome.html.

I believe that Mr. Cowan cited two aunts, Jane Davis and Roberta Davis, as being the sources for the oral history. Those names appear nowhere on the cited source.