A good family law attorney can handle more than just divorce and child custody cases. They ought to be able to advise you, at least in a general manner, on financial trusts, alimony, child support, civil unions, domestic partnership, adoption, and more.
Family law courts are usually the busiest in most jurisdictions, and often the most underfunded. If you're involved in a family court case, expect it to take a while to come to trial. Once it has, however, it will probably be dealt with very swiftly.