She grew up in the small town of Te Aroha in the Waikato before relocating to Feilding in the Manawatu region at age 9.
Kirby represented the Manawatu district at Miss Earth New Zealand 2007 where she was crowned the winner on 2 September 2007.
[2][3] Kirby represented New Zealand at the seventh Miss Earth beauty pageant held on 11 November 2007 at the UP Theatre in Quezon City, Philippines.
[4] Kirby crowned her regional successor, Samantha Elvy from Wellington, as Miss Manawatu 2008 at the Regent Theatre on Broadway, Palmerston North, on 11 July 2008.
[6] Miss New Zealand Festival of Beauty 2011 was held on 30 April 2011 in the Tasman Ballroom at Alexandra Park, Greenlane.