Children's charities, such as the Christina Noble Children's Foundation, have launched international appeals to help Mongolia's street children.

ECONOMIST: The street children are the symptom of a bigger problem

And like other supermodels before her, she's becoming her own brand: Last year, she collaborated with Momofuku Milk Bar to launch Karlie's Kookies, a line of vegan treats sold to raise funds for children's charities.

WSJ: The Kloss Family | Meet the Parents

Van Dyk has spoken out against the U.S.-led invasion of Iraq and has become involved in a number of children's charities following an emotional visit to the Indian city of Mumbai in 2002 where he was struck by the appalling poverty he witnessed.

CNN: Electronic Teutonic: Paul van Dyk