George & Bietz are brothers.
Minnie and Hulda are sisters.
Minnie Jensen Struve, George Struve, Hulda Jensen Grundmeier, Bietz Struve

Minnie (Jensen) & George Struve are the parents of Roy Struve.
Hulda (Jensen) Grundmeier is mother of Lorraine (Grundmeier) Hargens & Joanne (Grundmeier) Moore.
There were five children in the Clarence & Hulda Grundmeier family -- Grant, Shirley (McConnell), Lorraine, Joanne, and Gerald.

You can read more about Hulda (Jensen) Grundmeier on the Manning Centennial on the web -- click on the Manning Family - G 292 - 305 link on the left then scroll down to Clarence Grundmeier on the right.