In 1944 and 1945,  Katie's softball team, Bob Inn, won two Indiana state titles.  Katie spent the next eight years (1946-1953) in the All-American Girls Professional Baseball League behind the plate for various teams. Katie was a hard-working catcher with a quick release and a sure glove that paid off for her in the 1952 season when her Ft. Wayne Daisies won the League Championship.  In the off-season, besides competing in bowling and playing basketball, the business college graduate served as an auditor for an Insurance company and as a bank teller.  

After her playing days, Katie went on to receive B.S. and M.S. degrees in Physical Education from Indiana University and a Ph.D. from the University of Iowa.  Katie taught elementary, junior high, and high school physical education for nine years.  As Dr. Vonderau, she served as a full professor and chair of the Department of Health, Physical Education, and Recreation at the University of Wisconsin-Whitewater for 22 years.

Dr. Vonderau was inducted into the UW-Whitewater Athletic Hall of Fame in 1996.  In 2003, the University dedicated a permanent display case honoring her years in the All-American Girls Professional Baseball League.