I would like to locate my two half-sisters. My father (born in Kabul, Afghanistan) is their birth father from his first marriage to a Swiss born woman woman. My mother and father got married years after they divorced and had me and my brother. We have always desired to know our father's first children from his previous marriage. They may have different last names, which makes it hard to locate them. They must be in their 50's. Unfortunately my father passed away 8 years ago from lung cancer. He lost touch with his two first daughters when he left Switzerland.
How can locate my two half-sisters from Switzerland? We live in Southern California (Orange County).