Baby city somerset mall - verbally and physically aggressive when you complain

My wife brought defective items from baby city somerset mall and when she went back to change the items the shop manager got aggressive with her and my mother in law calling them dumb ****s. He said if they don't leave his shop he'll take them outside and show them what a real man looks like. My 6 months old baby and great grandmother was with them at the time. He said if they are not happy with the items brought they must take it up with the manufacturer....I'm taking legal and personal action against this baby city, the somerset mall store and the manager.