In many developing countries, some families find it difficult to provide new shoes for their children once they've outgrown their old ones.
This sometimes forces children to go barefoot, an issue when over two billion people in the world suffer from soil-transmitted parasites and diseases, according to the World Health Organisation.
But there may be a simple solution.
While living and working in Nairobi, Kenya, Kenton Lee noticed a little girl wearing shoes that were too small for her feet.
Asking why this was, he recalls hitting upon an idea: "Wouldn't it be great if there was a shoe that could adjust and expand – so that kids always had a pair of shoes that fit?"
This led Lee and his company, Because International, to create The Shoe That Grows, which expands in five sizes to last five years.
Using a system of sturdy snaps, the shoes easily increase in size. The shoes themselves are made from simple materials - leather, compressed rubber, and snaps. There are no mechanical parts or gears that could break, and they are easy to clean.
The company makes two pairs of shoes: one small and one large. Together, they say a child will have a pair of shoes to fit them from nursery age through to 14 or 15 years old.
To give kids a pair of The Shoe That Grows, the public can donate money to fill a duffle bag with 50 pairs of shoes.
Watch more about the initiative below:
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