It's been just over two years since Linda Stein was murdered in her apartment on the Upper East Side. Her assistant Natavia Lowery was charged with the crime and has been in custody sinceand now Stein's two daughters are suing Prudential Douglas Elliman brokerage for hiring her in the first place.The Real Deal reports that Samantha Wells and Mandy Stein "allege in a new wrongful death lawsuit that the city's largest residential brokerage hired Natavia Lowery, their mother's personal and work ass