Russel William Hesseltine or family info

i am the daughter of Russel William Hesseltine and Mary Adeline Stevens (sometimes went as bechtoldt). My brothers (Trent William and Ryan Quentin Hesseltine) and i are looking to find our father and that side of the family. Victims of the flower age of non-marriage, we are having some difficulties. Here is what we know. We have two older half sisters named carol and debra. we have an older brother adopted that carried the Hesseltine name, but stayed with his mother when she and dad seperated. Russel William Hesseltine is believed to have been born in Yakima WA on Nov 11, 1936 to mother Lucille (no known maiden)and father William Hesseltine. paternal Grandfather believed to be a Harry Hesseltine. and a Grandmother named Nora. We have reason to believe that Russel William was one of several children and had both brothers and sisters- Linda and sarah? among them.
We would appreciate any information whatsoever regarding this as there is no other way to contact. thanks