What one state could not get alone, what one miner against a powerful corporation could not achieve, can be achieved by the union.

To enforce worker solidarity Mary Harris Jones travelled to the silk mills in New Jersey and returned to Pennsylvania to report that the conditions Mary Harris Jones observed were far superior. As a union organizer Mary Harris Jones gained prominence for organizing the wives and children of striking workers in demonstrations on their behalf. She was baptized on 1 August 1837 which indicates Mary Harris Jones most likely was born in late July.

Jones worked as a teacher and dressmaker but after her husband and four children all died of yellow fever and her workshop was destroyed in a fire in 1871 Mary Harris Jones began working as an organizer for the Knights of Labor and the United Mine Workers union. From 1897 at around 60 years of age Mary Harris Jones was known as Mother Jones. In 1903 upset about the lax enforcement of the child labor laws in the Pennsylvania mines and silk mills Mary Harris Jones organized a Children's March from Philadelphia to the home of then president Theodore Roosevelt in New York.