Story highlights Three Illinois family members accused in decade-long shoplifting ring

Prosecutors say they stole more than $7 million in goods

How? By concealing the goods in the mom's big black dress

They face up to 10 years in prison, fines, restitution, if convicted

How do you swipe $7 million in toys, electronics and other stuff without anyone noticing?

Apparently, in Mom's flowing black dress, according to federal prosecutors who have charged three members of an Illinois family with transporting stolen property across state lines.

They'd been at it for a decade, prosecutors said.

Prosecutors say Lela Bogdanov stuffed merchandise in the blue lining of her big black dress, then walked out of the stores -- often with family members staging a diversion to draw the attention of employees.

The family -- Lela Bogdanov, her husband Branko Bogdanov, both in their 50s, and daughter Julia Bogdanov, 34 -- then sold many of the items to a fence who unloaded them on eBay, prosecutors claim.

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The alleged fence is cooperating with authorities and was not named by prosecutors.

The couple netted more than $4 million from the sale of stolen goods with a retail value of more than $7 million, according to the U.S. Attorney's office in Chicago.

The Bogdanovs' decade-long scheme began to unravel, prosecutors say, when loss-prevention experts at Barnes and Noble and Toys R Us noticed huge amounts of merchandise had gone missing.

They found an eBay account selling the same items in similar quantities as those allegedly stolen from their stores.

Secret Service agents arrested the trio Wednesday at their Northbrook, Illinois, home.

They'd just returned home from a trip to Oklahoma, Texas and Louisiana, during which prosecutors say they stole more items.

If convicted, they face up to 10 years in prison, a $250,000 fine and restitution.