You may be out of an inheritance if he has executes a valid will and leaves everything to his new wife.  If he marries and passes away and does not make a new will, his new wife/surviving spouse may elect to take against the will and get her statutory share.  Your father should execute a new estate plan that involves a new will and a trust and place his assets in the trust so he can provide for his new wife and also protect the inheritance of his natural and/or adopted children.