my sister just gave me her late husbands Iwatch......But I can't do anything with it since it's apparently paired to his phone..Any way that I can get to use this iwatch

She's in the hills of Montana, very slow internet connection. She has his log in, but not the password. She's waiting for the apple password reset message now. Maybe by tomorrow breakfast she will have it. Once she resets his password to something that she knows what it is. We may be able to unpair his Iwatch then I can pair it here in NY where I am