Born on a farm at Beaver Cove, NS and deafened at age 2 from whooping cough. Schooled informally 1892-1900, then entered school at the Institution for the Deaf and Dumb in Halifax, NS, graduating 1908 and continuing studies at the Victoria School of Art and Design until 1912, when she got a scholarship to study at the Boston Museum of Fine Arts in the U.S. 1915-1919, continued studying art and doing freelance illustration in New York City. Returned to Canada 1920 to teach art at the Halifax School for the Deaf; left in 1928 to get married to John Maxcy, a deaf American printer and moved back to New York. Worked as an illustrator for F.A.O. Schwarz until retirement in 1948. Beginning around 1952, she moved to New Hampshire and began to record her childhood memories in illustrations, and after her death a niece developed MacKinnon's illustrations and diary notes into a book, posthumously published as Silent Observer (1993).
Deaf Women of Canada, p.158-159.