A man and his wife own property, not as joint tenants, and he dies in 1981. Does the wife get his 1/2 interest, or she and their children?

What state is the real estate located in? That's the starting point. Under current Georgia law, the wife and children would split his 1/2 share in the property if he had no Will. I am not 100% certain if the rules were the same in 1981; I believe they were similar, however. If he had a Will, then the Will would determine what happens to his interest in the property. Most likely the wife did NOT receive the man's 1/2 interest unless either he had a Will which provided for her to receive all of it, or she filed a year's support claim and was awarded his entire interest in the property as part of the year's support claim. If this is a real situation in your family, however, you really should get legal help to determine what did happen and what needs to be done to clean up the title to the property as soon as possible, before the same problem just gets worse as the wife and children start dying off.