Breach in Employment Contract, Grounds for Law Suit?

My Sister was recently offered a job at a nursing home as a nurses aid, Full time benifits. She accepted the offer, and the employer asked for her paper work, drug tests, ect. Take note she was offered the job, and took it. After weeks of calling the employer to see when she started, the employer was too busy to answer calls, ect. After NO response the employer sends a letter in the mail, its a notice of how She was considered for the job and that she is not qualified enough. We are contacting an attorney to see if this is grounds for a law suit. She also quit her old job to work for the employer. I believe that the letter makes out that she was never offered the job, woulod this be a breach in contract, sicne she was OFFERED the job, and the lady said she would return her call to when she could start (she accepted my sisters paperwork) We are goign to sue for loss of wages, does this sound liek enought grounds? (My sister has proof of her hiring, by copies the employer gave her)