If my husband and his brothers where in a car accident, what would be a fair settlement?

Every case is different, so there are  no firm guidelines. That said, a rough rule of thumb is that if you were to sue and win, you might recover the sum or total of--

1) Medical bills actually paid by you (not by insurance), both to date and projected future (if the future bills can be proven sufficiently);

2) Lost wages to date and, if future earning potential is reduced (e.g. can't work at the same job or for as much money), the amount by which future earnings are reduced;

3) Other direct, out of pocket losses, such as if you had to hire a home health aide or housekeeper to help out for a time; and

4) "Pain and suffering" if the injury caused weeks or months (or more) of significant life impairment; for injuries lasting less than a year before being resolved, you can *very roughly* ballpark this at an amount more or less equal to your medical costs.

The above is what you'd get if you sued and win. If you settle before trial, you *always* take less--taking less is the other side's incentive to settle; and you get the money much faster and without having to pay for a lawyer, so you save money, which offsets the reduction in what you recover. (Also, trial is never certain--you could lose; but if you settle, you're guaranteed the money.) If you settle before trial, you'd typically get, say 1/4 to  1/2 of what you'd get if you went to trial; so figure out what you'd potentially get at trial and reduce it by 50% to 75% and that gives you a rough idea of a settlement. With that in hand, negotiate for as much as they'll give you.