Leaving Rotorua in her 20s she went on to work in a variety of roles for grocery companies including Goodman Fielder, L'Oreal and Pharmacy Brands.
"My favourite part was the creative side," she said. "I loved developing new products."
A near-fatal blood clot while pregnant with her third child forced a "life revision". Rather than rushing back to work she chose to take four years out to stay at home with the kids.
The idea for Water Buddies came about from a desire to get her own children to drink more water.
"They'd say 'water's boring we don't want to drink it'."
So she and husband Matt Clifford looked at what options there were on the market.
"Everything was really high in sugar, most of the juices contained the same amount of sugar as Coke."
With their kids' help they came up with the five Water Buddies flavours and characters as well as the bottle shape and logo. Two characters - Carter the Deep Water Robot and Milla in her Magical Crabsuit - are named after their children.
The brand was launched in New Zealand in October 2012 and this May it launched in Australia, where it's having "phenomenal success", she said.
Ms Leonard said they'd been invited to take part in a McDonald's review, which could see Water Buddies available in Australian McDonald's restaurants.
"It would be amazing if we could partner with McDonald's, we're all about offering a healthier alternative and McDonald's is working exceptionally hard to do the same."
They're also in talks with a large retailer in Hong Kong which would be a "nice way to dip our toe into Asia", she said.
This month they added the sixth Water Buddies flavour, Just like Lemonade, wrapped in a label which uses leading-edge glow in the dark ink technology.
Ms Leonard said the idea came from a mum on Facebook, whose son took his Water Buddies bottle to bed and would call out in the night when he couldn't find it.
"We said we need to make it glow in the dark," she said.
"We were the first in the world to do the technology. A lot of people told us it couldn't be done . . . but I am quite a determined girl from Rotorua. If you went to Sunset Primary you got told you could achieve anything you wanted to achieve."