Dollar Tree’s decade-long effort to fold the Family Dollar chain into its business is ending after agreeing to sell the bargain store chain to a pair of private equity firms for $1 billion. Dollar Tree Inc. bought Family Dollar with its over 7,000 stores ten years ago for more than $8 billion.

Dollar Tree is selling off its Family Dollar stores. Meanwhile, Dollar Tree is seeing increased demand among higher-income shoppers.

Assuming its new owner will actually fix what's actually ailing it, a new-and-improved Family Dollar will rattle the rest of the retailing industry.