Any Information

I am looking for information about my heritage. All I know is that my grandfathers name was Harold Wiltse and my fathers name is Robert Harold Wiltse. My father is 62 this year on December 2nd and he was born in California. My grandfather's wife was born in Minnisota. I know nothing else about my grandfather except he married a Downing. I don't even know my grandmothers name. Any information would be amazing!