In the meantime I found the descendants of my Aunt Olga Leontina. We have already met in Latvia and are in regular contact.
I am aware that the name Avotins in Latvia is a very typical frequently occurring surname, this also applies to other countries. A search and tracing for the descendants of my family Avotins line up to my grandfather, based on chance finds in any country, is close to impossible. My hope and only chance is that someone in the collection acknowledges his ancestors and take contact with me. Through my good contacts with Latvian State Historical Archives, search for more information would be no problem, but then the last option. This is also the same for the Paegle family line.