The couple considered them to be vulnerable because a mother cheetah can usually only provide for half of her litter and mortality rates are highest during the first 16 weeks of life.
However, in the months that followed, Kim and Hein were stunned to see the extraordinary relationship that formed between the cats and their two young children - then just two years and three months old.
Kim, 29, said: ‘I would be warming milk for babies and warming milk for cheetahs. I just kept feeding everyone.
‘When I was working, I would have them all in the office with me during the day and at night I would get up every two hours to feed them.
‘They wanted to be close to us because they didn’t have a mother and they were so much a part of our family that I would end up having the cheetahs and the kids in bed with me.
‘The kids saw them as completely normal. There was no difference in the way they treated the dogs or the cheetahs. They cuddled them like big teddy bears.’
As Wakku and Skyla got older and bigger, Kim and Hein created a new shelter for them in their back garden where they now live.
But the bond between the toddlers and the cats has remained strong as they have been bought up together - essentially as siblings.
The couple, not wanting to take any risks, also took special precautions - teaching their children how to play with the animals in a safe way.
Kim said: ‘The kids were taught not to run anywhere near the cats and when they walk, they have to face them. They are not allowed to turn their backs on them.
‘Our kids are small but they think they are dominant. If the cats jump or pounce, then they just push them down and say “No, don’t do that”, like other children might do to a dog.
‘The cheetahs are wild animals and their instincts are there. The kids realise they can’t just go into the enclosure to play with them whenever they want to.
‘It’s a lot of work in the beginning but it’s worth it.’