The origins of "Happy Birthday to You" date back to the mid-19th century, when two sisters, Patty and Mildred J. Hill, introduced the song "Good Morning to All" to Patty's kindergarten class in Kentucky. In 1893, they published the tune in their songbook Song Stories for the Kindergarten. Some[who?] believe that the Hill sisters most likely copied the tune and lyrical idea from other popular and similar nineteenth-century songs that predated theirs, including Horace Waters' "Happy Greetings to All", "Good Night to You All" also from 1858, "A Happy New Year to All" from 1875, and "A Happy Greeting to All", published 1885. However, it has also been stated that these earlier songs had quite different melodies.
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