[1] Au was born to a Chinese father and a Jewish mother;[2] her maternal grandmother is a Holocaust survivor.
[3] Au grew up in Toronto listening to her father's diverse record collection.
She started classical piano lessons at age six and started playing the alto saxophone in elementary school at Grade 7 at Claude Watson School for the Arts.
[6] In 2022 she joined the Ostara Project, an all-female jazz supergroup led by Jodi Proznick and Amanda Tosoff.
The Ostara Project has toured Canada throughout 2022 and 2023, featuring other musicians such as Laila Biali, Jocelyn Gould, Shruti Ramani, Rachel Therrien, Virginia MacDonald, Valerie Lacombe, and Marianne Trudel.