"We are not successful runners, more leisurely runners, nature runners. We wanted to get them fit and, of course, enable to join us."
"We mostly go hiking, mountain hiking and racing."
While the girls are proud of their medals and trophies their mother, Bieke Kostrewa, said they were "incentives which keeps them going".
The parents were quick to point out there was no pressure on the girls.
"[They] just run the course and if they don't want to complete it, that's good, but usually they do. It takes as long as it takes ... we don't promote it as a sport to achieve or be first, we want them to maintain fitness and to enjoy the joy of sports," said Mr Kostrewa.
Mrs Kostrewa said the running also promotes endurance and strength for their family hikes.
"We think kids should get into running and fitness, it's good for bone density ... they've got lots of energy so they have to move around a lot."
To encourage the girls Mr Kostrewa makes certificates for them for the bigger hikes they have done "to make it fun".
The family does not train for events as the girls do many after-school activities, including being members of the Lake City Athletic Club.
The family mix their hikes and races into their travels around New Zealand, said Mr Kostrewa.
"We incorporate it into the school holidays so we have some sightseeing and some races, and some walks and hikes.
"That's the good thing about New Zealand - it offers a lot of opportunities for outdoor activities and nature runs."
When asked by the Rotorua Daily Post what their favourite thing was about running, Marie and Sofie said it was having fun.
At the Podium Rotorua Half Marathon event in November Marie came first in her division for the 2km Kids Dash for girls under 7.
It's not just running races that the family take part in, with Marie and Sofie entering the Weet-bix Kids Tryathlon in December last year.
Marie and Sofie said they enjoyed having the difference of swimming and biking, but Marie said it was more fun to run together as a family.
Martin welcomed this viewpoint as "there's less logistics involved".
Coming up in 2017 they have more races planned, with the next race a half-marathon in Mt Maunganui in February for Sofie.
She was excited to run the full 21km alongside her dad, a distance Mrs Kostrewa said wouldn't faze her as she has run that distance, and further, before.
