Not really sure of death date. There is another Louisa Smith Butler that died in 1906, but she is Maria Louisa or Louisa Maria. 1900 US Fed Census states she came to US in 1835.
1870 US Fed Census 1900 US Fed Census
Found church documents of her death that identify her as Louisa Marie Butler https://www.ancestry.com/search/collections/2451
Found Louisa's full name signature on document allowing her daughter, Mary J. Butler, to marry at age 19. She is indeed Maria Louisa Smith Butler. https://www.familysearch.org/ark:/61903/3:1:S3HY-63V9-6Z5?view=index&personArk=%2Fark%3A%2F61903%2F1%3A1%3AQ29S-SW5W&action=view
Featured German connections: Louisa is 30 degrees from Johann Wolfgang von Goethe, 32 degrees from Dietrich Bonhoeffer, 31 degrees from Lucas Cranach, 28 degrees from Stefanie Graf, 29 degrees from Wilhelm Grimm, 28 degrees from Fanny Hensel, 30 degrees from Theodor Heuss, 20 degrees from Alexander Mack, 37 degrees from Carl Miele, 27 degrees from Nathan Rothschild, 29 degrees from Hermann Friedrich Albert von Ihering and 30 degrees from Ferdinand von Zeppelin on our single family tree. Login to see how you relate to 33 million family members.