Mark Staker argues that Alger lived with the Smiths between 1834 and 1836.
Mark Staker, Email, September 9, 2008, reprinted at "Joseph Smith and Fanny Alger," Joseph Smith's Polygamy, website, accessed December 16, 2021
Mary Johnson [daughter of John and Alice Johnson born in 1818] lived in the Smith home (Whitney Store) to provide assistance to Emma. She died March 30, 1833. Her death was unexpected and shook up the family. I believe Fanny Alger replaced Mary as household help for Emma. If that’s the case it is unlikely Fanny lived with the family while they were living at the store and it is unlikely she assisted them before mid-1833. She most likely assisted between 1834 and 1836, in their home up near the temple.