If this person didn't file for unemployment as soon as they were terminated, that was a real bad move, since it's been six months. Available wages to set up a claim may be really reduced by now, if the person has not gotten another job.
If they did file for unemployment benefits, the company would have had to give some reason for the termination. If a person consulted with an attorney under these circumstances, the first thing the attorney might suggest is that they file a claim for benefits, to see what the employer is going to give as their reason for doing the termination. It will help to verify if there was some cause given, or if the employer will simply say it was due to a lack of work for the employee, etc. Filing for unemployment benefits if the employer did not have a valid job related misconduct reason to terminate is probably going to be the only recourse that is available to this person. Just because they are over 40 does not mean they can't be fired. It just means there might be a pattern of discrimination if the company makes a habit of firing their older workers for no good reason.