You will not find any information on Ursula Brand (*1925) on any official web site, and the chances that a reader of this forum knows about her is extremely dim. So your only realistic chance to get on with your research is to contact the Civil Registry Office of Stammheim, her place of birth, the Zivilstandsamt Bezirk Andelfingen. Ursula Brand's birth will be registered there - but Stammheim is not the "Bürgerort" (place of citizenship) of her parents. Ask there whether they will give you her parents' "Bürgerort" - or what you have to do (and pay) to get this info. Once you have this info - let us now.
Only the BRAND family should be discussed here.