The way MT "performs" his signature in this 13 February 1868 letter to Olivia L. Langdon indicates how much he could invest in a name. This is the first time he's written Livy after their engagement became official, and he recognizes his new status as her accepted suitor by cancelling the last four letters in the signature he has been using at the end of letters to her, "Saml. L. C." He thus turns himself into "Sam." "Sam," as you can see on another letter, was the name he used on letters to his mother, brother, sister and other family members. Most of the hundreds of letters he wrote Livy for the rest of her life are signed either "Sam," or "Saml."
The editors at the Mark Twain Papers identify the "absurd cousin" he mentions as Harriet Lewis. Mrs. Fairbanks was the Cleveland woman he addressed as "godmother." He typically signed off his letters to her as "Your Cub," as in "cub pilot": she was teaching him how to navigate the currents of genteel Eastern society.
This page appears here with permission of the Mark Twain Papers, UC Berkeley. To see the entire letter, with annotations by the Project, use the link below right, and search for MS: CU-MARK, UCCL 00247.TRANSCRIPT OF THIS PAGE | MARK TWAIN PROJECT