The outing comes just a few weeks after Mallette, 40, attended her son's concert at the Staples Center in Los Angeles, California. "What a great show @justinbieber!!!!" the proud mother tweeted at the time.
A source also told ET that Mallette left Hawaii, where she lives, to meet her son in Canada a few weeks ago.
Mallette and Bieber have been spending more time together this year, but the "Sorry" singer did admit no too long ago that he was estranged from his mother for a bit. In an interview with Billboard magazine last November, he blamed his deteriorating relationship with Mallette on his headline-making bad behavior.