My grandmother died without a will do it was to be split between my aunt and gather and since he has passed

I'm not sure I'm following.  Here's how I'm reading it:  your granmother passed away and was survived by your father.  Your father passed away some time after your granmother.  he had a will and left his estate to his current spouse.  Is that correct?  If so, the only contest here would be to your father's will.  The contest would have to be based upon an allegation that he was unable to prepare a will due to some impairment that adversely impacted his ability to understand what he was doing when he created the will.  If he had no such impairment, then there would be no valid basis to contest the will based upon his decisions about to whom to leave his estate.