Hmmm ... for my two cents ... I'm not a big fan of lawsuits. I personally think that we as a society have gotten way overboard on the whole matter of suing anybody and everybody else for their errors (real or percieved).
Now, don't get me wrong, what happened to your mom was piss poor and a classic example of atrocious human resource (and human relations) practices on her former boss's part. And, yes, it does create a significant financial burden upon your family. Nobody asked for that, nobody wanted that, nobody planned for that... but it's reality now.
However, also keep in mind the economy and the fact that people all over the place are losing their jobs. It seems that every other week, someone on this forum posts up about their own job loss. Companies everywhere are shaving people to cut costs and because their business is down, they can't afford those people anymore. I don't know about the financials of your mom's former employer, if they're swimming in money or not. But being a boat yard and given how the boating industry as a whole tends to tank during economic hard times (since boats aren't exactly a necessity for most folk), I would tend to believe that they're hurting and looking for ways to shave costs and your mom unfortunately wound up in the cost-cutting cross hairs. Though her former boss's wife now has her job, I'd ask the question of if the boss's wife also has the salary. Is she actually getting paid what your mom got paid to do the job ? Or is she working "out of the goodness of her heart" for her husband (for free or reduced rate). That's something the boss can ask his wife to do ... not an unrelated employee. On the other hand, if the boss brought his wife on board to boost the family income level and help her support her spending habits, then that's another issue.
In addition, I don't know what your mom's working relationship with her boss was like, if it was good and amicable or if it was strained. If it was strained, then this probably shouldn't have been unexpected. If it was good, then her former boss has communications issues, plain and simple.
I'm not gonna stop you from seeking out a lawyer, depending on your state's laws, you may or may not have a case. However, though your moms' former boss may have communications issues, I'd weigh the circumstances of her firing, if it was done to save the company ... or done to save the boss's wife's spending habits. If the former, a lawsuit might not be the best option. Suing them when they're out of money will just land you in the middle of a bunch of legal bills and no payout. And if you go contingency (lawyer only gets paid if he wins) then expect to see 1/3 to 1/2 of your winnings get siphoned off in legal fees. That, and even if you do win, do get paid and the boss is down on cash, then someone else (or multiple someone else's) may lose their jobs at the yard as well to finance your payout. If the latter ... well, I'll let you decide.
And if you do decide to sue, as others have said, not so sure that you would want to sue for the old job back. Does she want to go back to work for that guy ? A nicer severance package might be a better bet ... and something like that can often be done out of court and, depending on the conditions, might not even require a lawyer.
