Career
Millynn was part of New Zealand U17 roster who played in the 2010 Fédération internationale de football association U-17 Women"s World Cup. She appeared in two matches. She was also a constant presence in the New Zealand U20 team
She was part of the roster in the 2012 Fédération internationale de football association U-20 Women"s World Cup, where she played three matches and scored one goal.
Millyn was also in the roster that represented New Zealand in the 2014 Fédération internationale de football association U-20 Women"s World Cup, she played matches for her country. In 2015, she was called to the New Zealand 23-roster that will play in the 2015 Fédération internationale de football association Women"s World Cup but was an unused substitute.