Hal,
Interesting and appropriate question.  I gave a paper on this topic at ALA a few years ago.  I'll try to dig it up and send it along to you.
The quick answer is that there is no evidence I could find that Twain ever used that phrase, nor did the first (or second) generation of biographers.  The first time I can confirm that the phrase appeared was in 1960, and as the 20th century went on, it appeared more frequently, and with assurance, by many Twain critics and biographers.
What also emerged in my research for the paper was that Livy and Susy's bond was fierce, and the effect of Susy's death on Livy dominated the family for a very long time.  If Susy was a "favorite," I'd apply that term to Livy, not SLC.  But knowing what I know now, I wouldn't use it at all.
Linda
On Jun 19, 2014, at 10:07 AM, "Lee, Judith" <[log in to unmask]> wrote:

> This is an interesting question, Hal, especially in light of research on birth order and parental investment—that is, on social and biological forces outside of individual biography.  Of course Langdon was the first born, but since he did not survive long, Susy as the oldest held that privileged position, well known for the intensity of parental investment of time and care (the parents among us can check our own photo albums for the overabundance of baby pictures of the oldest kid, compared to younger ones!).
> 
> I think of this first-born bias often when I hear parents who’ve sent their oldest child to a big-name private college express the sense they got pushed into a prestige choice that they would not make for a younger one. But these are just anecdotal responses to underscore my sense that many factors may have given Susy a privileged place in the Clemens family and Sam's heart even apart from her evident charm, intelligence, and literary ambitions.
> 
> Judith
> 
> 
> On Jun 19, 2014, at 10:14 AM, Hal Bush <[log in to unmask]<mailto:[log in to unmask]>> wrote:
> 
> Folks;  one of the old chestnuts of Twain biography, I suppose, is the
> notion that Susy was his  "favorite child" or "most favored daughter."  I
> am among those who have said as much.  Now, working through this material
> once again, it strikes me--was she??  I'm fairly certain there are quotes
> to that effect but I am presently unable to unearth any.  I'd be happy to
> quote from various biographers and critics to that effect but I think most
> of you get the picture.
> 
> Can we say for certain that Susy was his favorite?  Or is that another
> effect of the echo chamber of earlier scholars and biographers?  Opinions
> and/or actual evidence is invited... --Hal B.
> 
> --
> Prof. Harold K. Bush
> Professor of English
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> 
> My newest book: Twain's Brand:  Humor in Contemporary American Culture <http://www.ohio.edu/people/leej/Twains_Brand.html>
> 
> Judith Yaross Lee, Ph.D.
> Professor and Director of Honors Tutorial Studies
> Director, Central Region Humanities Center
> School of Communication Studies
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> 
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