Who is this person?

[Anita]

Roger, but you're near enough!!!

Chester Arthur's wife Ellen died at age 42, January 14, 1882. Six months later Arthur was nominated as VP on the ticket with Garfield. Garfield and Arthur won the election on 2 November 1880, and assumed office on 4 March 1881. Six months later, following the death by assassination of President Garfield, Vice President Arthur assumed the presidency, sworn in at his Lexington Avenue home.
The person pictured in post #1916 is his sister Molly McElroy. When Ellen Arthur died, son Arthur and daughter, Molly were looked after by Chester's sisters. McElroy took he over supervision of her niece Nellie. Arthur, now President went a year without a First Lady.

Tenure as First Lady
41 years old
14 January 1883- 4 March 1885

Chester Arthur’s desire to have his daughter Nellie now live permanently with him in the White House was the determining factor which led to the girl’s supervisor, his sister Molly McElroy, serving as his First Lady, but tracing the progress of her presence evidences that he came to appreciate the value of a designated First Lady.
Go here to read how McElroy transitioned into the official role as First Lady and her many accomplishments. Also included, Ellen Arthur's biography. http://archive.firstladies.org/biographi...ography=22