"We've formed an incredible bond and it's amazing how many ties we have discovered. For example, Alexis was bubbly like our daughter, Courtney, while one of Chrisjan's favourite household chores was feeding the piglets and we breed pigs - then there's the fact that our grand daughter's name is Alexis."
Leanne says it was not long after talking to the families that Clayton hatched the plan to create Wallowing Heights.
"The idea of providing a place for children where they could laugh, have fun and learn about animals seemed to fit in with their view on life. We had the animals already, and it seemed a fitting way to remember them both."
Armed with pen and paper, Leanne said she took her "scribblings" to the team at East Taratahi Building supplies and they helped her create her dream.
"Yellow was Alexis' favourite colour, while Chrisjan loved red. We have incorporated these colours throughout. The yellow and red fence around the children's garden symbolises them being united and together protecting this area for youngsters."
Wallowing Heights, which is the Browns' pig stud name, also features miniature ponies, which children can ride, as well as pedigree pig and sheep breeds.
There is a viewing shed, which Clayton says serves a double purpose as all the animals can be brought into the shelter in rough weather.
Information about each of the breeds adorns the walls, allowing children to learn about the animals they are seeing. As well as the larger animals on show there are also chickens and rabbits to keep the youngsters amused.
The couple has also planted a selection of 11 fruit trees in memory of each of the balloon victims.
Wallowing Heights was officially opened on Saturday morning by Carterton Mayor Ron Mark, and attending the private opening were representatives from several families who lost loved ones in the balloon tragedy.
Alexis' parents, Vivienne and Allan Still, from Wellington, and Chrisjan's father Jan, from Southland, unveiled the children's garden and cut the ribbons - yellow for Alexis and red for Chrisjan.
Jan, whose wife Annie was unable to attend, is delighted with the result.
"I'm really happy. While this was a place where our children spent their last moments, it is now a place where life goes on - after all, the young ones who will play here are our future. This garden will soon be filled with the sound of kids' voices and their laughter," he said.
Allan echoed Jan's comments, saying: "The tragedy is still raw in our minds and our hearts, but what Leanne and Clayton have done is quite amazing and I hope the people of Carterton support them."
Wallowing Heights will be open weekends and school holidays between 10am and 4pm, and weekdays by arrangement.