Euroa state Nationals MP and deputy party leader Steph Ryan has announced she is quitting parliament.
Ns Ryan will not recontest Euroa, at the upcoming November state election.
"With a little one at home and another on the way, it is time for me to seek a job that offers greater flexibility," Ms Ryan said.
"Serving my community as the first member for Euroa has been the honour of a lifetime.
"The greatest pleasure of this job has been the opportunity it has afforded me to meet every day people doing extraordinary things.
Ms Ryan served as deputy National Party leader for the past eight years and was the first woman in the party's history to be elected to a leadership position, at a state or federal level.
"I believe our community deserves someone who can devote 150 per cent of their time and energy to representing them," Ms Ryan said.
"In reality that means someone who can give freely of weeknights and weekends and that, at this stage in my life, is not compatible with my wish to be more present for my family."
National Party leader Peter Walsh said Ms Ryan had been a driving force for positive change for regional Victorians during her time as MP and deputy Nationals leader.
"I know this is not a decision she's come to lightly," Mr Walsh said.
"Like so many of our regional leaders, Steph was motivated to step up to be a voice for change after witnessing the desperate neglect and inequity in decision-making on challenges that are facing rural people.
"Coming from a dairy farming family, Steph's was one of many who struggled with the devastating environmental, social and economic impacts of the millennium drought."
When elected, in 2014 at 28, Ms Ryan was the youngest MP in state parliament.