Can my father write a Will without including any share for my wife?

I got recently married. My father did not inherit any property and earned property worth 1.2 crore including savings. My relations with wife and in-laws are not good. My father wants to write a will in such a manner that my wife and in-laws can never lay their hands on it. Is it possible? He wants to include in the will that the property should never belong to my wife's family.