Morrissey akamirira Canada mumakwikwi akawanda epasi rose, kusanganisira IIHF World U18 Championships, Ivan Hlinka Memorial Tournament uye IIHF World U20 Championships. Morrissey akabatsira timu yeU-18 kuhwina goridhe ku2013 IIHF World U18 Championships
, pamwe nechikwata cheUnder-20 pa2015 World Junior Ice Hockey Championship. Akasarudzwa ku2015 World Junior All-Star First Team, achipedza aine mapoinzi mana uye +9 plus-minus rating.