VIDEO : Audrey Hepburn's Children Lend Rare Photo Collection to Exhibition

Audrey Hepburn was a Hollywood legend, a style icon and in her later years an ambassador for UNICEF.
Her two sons have lent rarely-seen photographs of Audrey Hepburn, from their personal collection, for a new exhibition.
It opens this week at London's National Portrait Gallery, and explores the life and career of the celebrated star.
Her youngest son, Luca Dotti took the BBC's Arts Editor, Will Gompertz, on a tour of his personal favorites.