U.S. law enforcement's decision not to charge anyone in the death of Shanquella Robinson has her family outraged -- but they're not ruling out a lawsuit to seek justice in civil court. TMZ spoke to the late North Carolinian's mother and sister -- Sallamondra and Quella, respectively -- who told us how they're feeling in the wake of last week's news that U.S. officials are closing the book on this case without holding anyone accountable.