What if a will is not probated and there may be property involved from ones deceased spouse

If the brother passed away, there may not have been a need to file his will if he owned everything jointly with his wife.  The decision not to probate the brother's wll may have been done without condering the other property.  Another answer may be that when the parents died, and lef the property to his children with life rights for one daughter, the ownership of the property might have been changed so that when the brother died, his rights passed to the other siblings.  you should get a copy of the deed to the parents property and see if the surviving siblings get the property.