If the son lives in a state that allows deficiency judgments, then yes, the mortage company can get a judgment against him for the balance of the mortgage that they do not recover in selling the home. A deficiency judgment can ultimately allow the mortgage company to garnish his wages. With the significant number of defaults and sad shape of the housing market these days, mortgage companies are pursuing deficiency judgments more and more because they’re left with 50% or more of the loan balance unrecovered at auction.
Obviously, ditching a mortgage will adversely affect his credit - usually by 250 - 300 points.
Thanks to all who are providing responses. I am forwarding all your comments via email so that they can process through these.
The comments regarding the mortgage co. holding him responsible is one of the things I told my pal that might happen. I know that is normally what happens if you have a car repossessed.