In the most recent episode of his podcast Stanley25, Maxime Truman provided the answer, while remaining within the realm of public information.
Let's remember that last Saturday, David Savard accidentally revealed during a live TV interview that the head coach of the Canadiens had left to be by the bedside of one of his three sons, as reported by Marco Normandin.
Maxime Truman indeed revealed, during the most recent Stanley25 podcast, having found a post from the Mid Fairfield 08s team, in which his youngest son, Mason St. Louis, plays.