She grew up in Oakville, Ontario with her younger brother Nicolas William Boris Bjorn Petrick; their parents met playing tennis.

[3] In July 2011, Petrick played her first professional tournament at the $50k WOW Tennis Challenger but lost in the qualifying first round to Nicola Slater.

[5] In August 2012 at the age of 15 she won the Under-18 Canadian National Championship, beating Gloria Liang in straight sets (6-3, 6-4).

[7] Petrick made her WTA Tour debut in September 2014 at the Coupe Banque Nationale, having received a wildcard with Sonja Molnar into the doubles tournament where they lost to Barbora Krejčíková and Tatjana Maria in the quarterfinals.

[8][9] Petrick was once again awarded a wildcard into the doubles main draw at the 2015 Coupe Banque Nationale in September, this time with Malika Auger-Aliassime, but was defeated in the opening round by Barbora Krejčíková and An-Sophie Mestach.