For a working mom, entrusting a child to a nanny always involves a scary leap of faith -- and comes with a nagging, incessant worry. Former supermodel Cindy Crawford saw her worst fears realized when her young daughter, Kaia, became the target of a chilling blackmail scheme that's consumed the family for four months.

Back in July, federal authorities say, Cindy and her husband of 11 years, Rande Gerber, received a terrifying phone call from model Edis Kayalar, an acquaintance of their former nanny. Kayalar claimed he was shopping around a photo that the nanny had taken of Kaia, then 7, "in revealing clothing, bound to a chair and gagged," according to authorities. Desperate for help, Rande and Cindy called the police. The authorities managed to deport Kayalar, who had reportedly overstayed a tourist visa, back to his native Germany. But even then, the nightmare didn't end. Shockingly, on Nov. 1, Kayalar e-mailed the couple and demanded $100,000 to keep the photo private.

Kayalar has been charged with extortion and could face two years in prison. But the ultimate betrayal came from the nanny, the person Cindy and Rande entrusted to care for Kaia, now 8, and their son Presley, 10. "Their kids mean everything to them," an insider tells Life & Style.

For more details on the extortion case, pick up the latest issue of Life & Style, on newsstands today!

Photo Credit: Retna