@Jimmy_K2 - sure but if the FIL goes after the estate while the son sits back and watches, what exactly is the son doing?  The son is making the FIL spend money on a lawyer to get something he feels is rightfully his.  Whether he wins or loses, the son looks like he wanted to keep the money.  The son has 2 choices:  Give the proceeds to his Dad or say sue to get it.  It doesn't matter who gets sued here.