Patti Petersen Mirkovich (born December 2, 1954).
Patti Petersen Mirkovich, formerly known as Patty Petersen, is a retired American actress. Her brother, Paul Petersen, co-starred on ABC's The Donna Reed Show. Patty was written into the cast as Trisha, an adopted child after Shelley Fabares left the series. She stayed with the show until it ended in 1966. She first appeared in "A Way of Her Own" (S5:E20).
Patti serves on the Board of Directors of The Donna Reed Foundation.