27 January 2012: The eurozone crisis casts a chill over every conversation with the bankers and businesses in Davos this year. But there are some stars here guaranteed to warm the heart.

I had the privilege of hearing one: Archbishop Desmond Tutu on child marriage.

Despite the seriousness of the subject matter, his smile and self deprecating humour lights up the venue - the UNWFP tent, which is in a local community hall.

Passionate plea

Tutu at 80 plus is as passionate about ending early child marriage as he was about combating apartheid. Now a grandfather many times over, he tells a spellbound audience of a conversation with his 15-year-old granddaughter who he realises could in other circumstances be married against her will.

Every year millions of children are married, sometimes as young as 8. In the hour and a half the luncheon takes (organised by The Elders and the UN's Every Woman Every Child campaign), 1,700 children will be forced into early marriage.

Childbirth deaths

Tutu - or the Arch as he is affectionately known - gently chides the UN Secretary General who is present at his table about the Millennium Development Goals. "What chance for these girls?", he says. Married too young they will often die in childbirth, have sickly premature babies who will never attend primary school, and are more likely to get HIV and AIDS.

And the advocates The Elders* assemble in their video - Tutu himself, Mozambican politician and humanitarian Graça Machel, and the former President of Ireland Mary Robinson - whilst acknowledging the social forces which sustain child marriage, never allow them to justify it.

Early marriage is a root cause of poverty issue and one we all have to keep in the public eye.

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