In 1992 nearly every world leader travelled to Rio for the United Nations Conference on Environment and Development - the 'Rio Earth Summit' - designed to protect the world from continuing destruction. Here, world leaders made promises to protect the environment and safeguard it for future generations.

This week's Earth report follows the lives of two children born at the time of the Earth Summit to see how the changing state of our planet, and how the promises made in Rio, have affected them. This is the story of Erdo and Kay Kay.

Erdo: life in rural Kenya

Erdo was born in Kenya to Esther and Christopher - nomadic herders of the Turkana tribe. The Turkana way of life has changed little over the years but changes in the environment are forcing them to reconsider their herding lifestyle. In 1992, life was changing on the plains of northern Kenya.

When Erdo was born his family had just survived one of the worst droughts anyone could remember. Spiralling population pressure was taking its toll on scarce grazing land and the drought, when it hit, contributed to the severity of its effects. And these desperate times had also brought with them new dangers; raiders.

When the film crew caught up with Erdo's family they had narrowly escaped attackers from a rival village who had sacked their homes and school, stolen their cattle and killed an uncle and an older brother. Climate changes and an increasing pressure on land were beginning to usher in a new, desperate, more violent society. For three month old Erdo this was the start of a life of turmoil.

Two years later Erdo was still living with his family but their herding way of life had got harder still. Heavily armed bandits now threatened to steal their cattle and Esther's relationship with her husband had deteriorated as she lobbied for Erdo to receive an education to break their cycle of poverty.

To make matters worse, the continuing drought had forced elephants out of the wildlife reserve in search of food and to make ends meet, with an ever growing family, Esther had turned to producing charcoal - helping to turn the bush into a desert in order to buy grain.

As Erdo reached his eighth birthday his circumstances had changed yet again. Esther and Christopher had separated and Erdo was now living with his father's first wife. Christopher was still pursuing a herding lifestyle but was now heavily armed himself. Esther had left her nomadic roots behind and was now farming a small plot of land, the earnings from which she invested in a microcredit scheme. If she makes enough profit she will buy a desk for Erdo so that he can return to her and go to the local school. Until then, Erdo continues to live separately, travelling many kilometres to a Korean Missionary school where he has begun his education.


Kay Kay: life in industrial China

Kay Kay was born in 1992 in one of the world's fastest growing cities, the southern Chinese city of Guangzhou.

The Earth Summit was supposed to help show the way for countries like China to develop in less damaging ways but pollution levels are still sky-high. China burns more coal than any other country in the world. This means that in industrial cities like Guangzhou, Kay Kay and her generation are six times more likely to develop lung cancer than her counterparts living in the cleaner air of the countryside.

China's race to industrialise may have economically transformed the lives of those living in her major cities but the environmental and social cost is high.

China's 'one child per family' lawmeans that Kay Kay's parents can spend more of their earnings on their daughter, but life in Guangzhou is still hard for Kay Kay. Although her parents earn more than ever before they must work long hours to get it. As a result, Kay Kay spends much of her family life alone.

As Kay Kay grows older we see that Guangzhou's growth has continued unabated. Now it's a city of five million people and pollution levels are still rising. Traffic fumes are now a major contributor to pollution and pedestrians have to wear masks to breathe.

And Kay Kay's family life hasn't changed. In order to survive her parents are still working long hours and they are lucky to find time to share a meal together once a month. Kay Kay has learnt to live with little contact from her parents.

Kay Kay and Erdo may live in vastly different worlds, continents apart, but they both have fragmented families. Eight years on from the Rio Earth Summit we are perhaps seeing a pattern emerging. As population pressure on the world's environment increases, our children are paying the price.