His daughter is now 5 and he told the Dannevirke News his family "aren't going anywhere".
"I am here for the long term," he said. "We came down to be part of the community and community groups and iwi supported me in my application for the position.
"We like it here. We have a lifestyle block and my daughter goes to a good country school, so why not live here. Dannevirke has worked out very well for us. This is a good community and Dannevirke has a lot going for it."
But McKernon admitted there isn't any map to follow for his new role, with issues, like any town.
"Family harm issues are complex and getting to grips with this is a new challenge," he said.
"Victims are nearly always the children and when you listen to some of the stories ... "
After 23 years on the beat, McKernon has seen some of the horrific sides of life, including women who took a beating to appease their husbands and to protect their children.
"When I first came to Dannevirke youth crime was huge, but the installation of CCTV security cameras have made a big change," he said. "Now I'd like to see us deal with the tagging."
McKernon said the perceived gang problem in Dannevirke was complex too.
"These gang members have lived here longer than me, they haven't moved here," he said.
"Wearing a gang patch isn't a crime, but when they commit an offence they are caught and charged."
Tararua's Senior Sergeant Jymahl Glassey said police were trying to deal with a perception by the public about the gangs, rather than unlawful activity.
But it's difficult for police to manage that perception, McKernon said.
"We've had feedback regarding our visibility in town and it's my intention to have more foot patrols, with police more accessible," he said.
Glassey said he's pleased with McKernon's promotion to sergeant and his new role will have a strong focus on community engagement and crime prevention.
"Gary is ideally suited to this role and his strength is his ability to relate to people and to follow through," he said.
"That's what our community needs. Gary's new role gives us an ability to continue with crime fighting and things which make our community safe and connected."
For McKernon, living and working in a small town means his profile is high.
"People know us and it's good to be here and known," he said.
McKernon's position is the second sergeant's role with Paul Adrian also based in Dannevirke.
But two staff have left the police in town this month and another has returned to Palmerston North for career reasons.
"This did impact our staffing levels but we have managed to recruit to fill those positions, so there's no loss," Glassey said.
Over the past six months Dannevirke has seen a good reduction in property crime and a lot of that is down to the focus of police, but drug and alcohol problems remain.
"Drugs and alcohol are a way of escaping and getting a sense of euphoria and is most prevalent in our lower socio-economic groups," Glassey said.
