News that “Happy Birthday to You” may be in the public domain after years of copyright tussles has raised hopes that the song may finally become available to television and filmmakers unwilling to pony up a hefty fee for its use. But who was behind the song that’s now so lucrative? It turns out one of the song’s driving forces was Patty Smith Hill, an innovator in early child education.

Hill’s Phi Lambda Theta obituary mourned her death as the loss of “a leader in the progressive education of young children.” It tells the story of how Hill rose from kindergarten teacher to professor of education—a rise that was driven in part by the Progressive Era.

Like many women of her time, Hill was inspired by the chance to help upend traditional wisdom on education and work with poor and underserved communities. Her obituary notes that she literally threw away the detritus of past teaching methods, ditching small toys and substituting building blocks and large print materials instead. Her other innovations reflect Progressive Era concerns: providing medical supervision, basic sanitation, running water and “scientific cleaning” to children.

Dorothy W. Hewes writes that Hill found a way to work within the gender strictures of her time to create real change. Her kindergartens provoked furor for their “free style” and philosophy that rather than being a tool to be molded by teachers, children had their own capacity for growth. These beliefs led to child study, playgrounds and even psychoanalysis.

Music was part of that philosophy, too: together with her sister Mildred, she published a book called Song Stories for the Kindergarten and Primary Grades that focused on less traditional songs that could easily be sung by young children. Among them was a song called “Good Morning to All,” the tune to which later became “Happy Birthday to You.” Though it’s unclear whether the Hills actually wrote the melody or just transcribed it, the song’s popularity is in its simplicity—a simplicity that would have been at home in a nursery school classroom.

Hill’s legacy lasted much longer than your typical birthday candle: in fact, she was a key figure in what is now the National Association for the Education of Young Children, and her philosophies about the potential of small children still resonate in kindergarten classrooms to this day.

Image: “Good Morning to All” the song that became “Happy birthday to you”