I am a great-granddaughter of Wilhelm Weinberger. The marriage certificate for Wilhelm and Barbara lists his mother as Maria Katherina Muther. The date of certificate is 12 Sept. 1865 and they were married in Madison, Wisconsin. I don't have any more information on her.
However I have many Gansers in my tree.
I am having a Weinberger reunion in Regent, ND on July 6. If interested, contact me.