WHO IS REX PATRICK?:
* Born in New Zealand in 1967 and moved to Australia with his family aged seven.
* Educated in Whyalla before leaving to join the Australian Navy at age 16.
* Volunteered to serve on the Oberon Class submarines and later joined a trial crew on the first Collins Class submarine.
* Left the navy in 1994 after serving for 10 years and worked for an Australian sonar design and development company as a trainer, then project manager, business development manager and head of research and development.
* In 2007 Mr Patrick started his own company building a successful domestic and international business in sonar and acoustics training.
* Joined the Nick Xenophon Team at the start of 2016 as a senior adviser before being asked to fill the casual vacancy in the Senate caused by the resignation of Senator Xenophon.