I'm not related but have found some information that should help you.
The South Dakota Marriage Index at Ancestry shows Otto Schnaible and Alice Overseth were married in Sept 1934.
In 1940 they were living in Java, Walworth SD with 2 children. The marriage didn't last and in 1949 Otto remarried. He is listed as divorced. He and his wife remained in Java and he died there in 2001. Alice appears to have married twice more and died in Placer Co. CA.
I will send you an Ancestry message with further information. If that doesn't help there are several trees on Ancestry with Otto in them and you can try and contact the tree owners.