On 29 June 2005, Willoughby made her test debut for the Black Ferns against Scotland at the Canada Cup in Ottawa.

[3][4][5] Willoughby was member of the Black Ferns squad that won the 2006 Women's Rugby World Cup.

She played her last international against the Wallaroos on 18 October 2008 at Canberra, it was the final match of the Laurie O'Reilly Cup.

[10] Willoughby was instructed by Matthew Greenslade when she obtained her commercial pilots' license from Ardmore Flying School in 2011.

This biographical article relating to New Zealand rugby union, about a person born in the 1980s, is a stub.