Gravel was born in Berlin, Germany but grew up in Asbestos, Quebec. He is the son of Francois Gravel, a former professional ice hockey goaltender who was selected in the 3rd round, 87th overall in the 1987 NHL Entry Draft by the Montreal Canadiens and also represented France in the 1998 Winter Olympics. Gravel was inspired to play goaltender because of his father, and began playing when he was around five years old, first playing in Italy where his father played for 12 years.