Ronny Hallin was a producer and casting coordinator who worked in television. She collaborated with her brother Garry Marshall on Happy Days, Laverne & Shirley, and Joanie Loves Chachi. Hallin was also a coordinating producer on Perfect Strangers and Family Matters in addition to being a producer on The Hogan Family.
Hallin's work as a casting coordinator included stints on such television series as Mork & Mindy, Happy Days, and Laverne & Shirley. She was also a casting consultant on Who's Watching the Kids and The New Odd Couple.