Labor strategist Magenta Marshall has been selected as the party's candidate for the seat of Rockingham left vacant by Mark McGowan.
Ms Marshall started her political career as an electorate officer to Balcatta MP David Michael six years ago.
She then became a campaign strategist in 2021.
Ms Marshall is aged in her late 20s and has spent her entire life in the Rockingham area.
She currently lives in Waikiki with her husband who is a teacher.
"We love our local community, and I am looking forward to the opportunity to represent Rockingham in the Roger Cook Labor Government," Marshall said.
Ms Marshall has a degree in Asian Studies and Politics and International Relations.
During her studies, she spent a semester abroad studying at Gadjah Mada University in Yogyakarta, Indonesia and taught English at a local school.
She is also involved in local sports and is now a member of the Baldivis Football Club where she is the Assistant Coach for the women's team and a youth mentor.
The WA Liberals are yet to put forward a candidate but did confirm they would contest the by-election.
Rockingham residents will take to the polls on July 29.
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