"To Rome With Love," a situation comedy series starring Johin Forsythe as an American college professor living in Rome with his three young daughters, premiered Sunday, Sept. 28, 1969 (7:30-8:00 p: m.) in color on the CBS Television Network. Kay Medford, popular comedienne of stage and movies, is costarred as the professor's older sister. Featured as the daughters are Joyce Menges, Susan Neher and Melanie Fullerton. The series concerns the adventures that befall Professor Michael Endicott (Forsythe) when he decides on a change of scene for his girls following their mother's death. He takes a job teaching at the American Overseas School in Rome. There the family finds itsef in a constant whirl as it adjusts to new ways and people. As Professor Endicott, Forsythe has the task of not only keeping track of his lively daughters but also handling such problems as the "generation gap" and getting a settled home life in a bustling Italian neighborhood. Forsythe is a veteran of two previous television series, "Bachelor Father" and "The John Forsythe Show." He has starred on Broadway and i n many motion pictures, including "The Trouble With Harry," "In Cold Blood" and "Topaz." Miss Medford, as Aunt Harriet, provides a steadying influence on the girls but has her own problems in the foreign atmosphere. Miss Medford won an Oscar nomination as Best Supporting Actress in the movie "Funny Girl" and has played in numerous Broadway musicals and motion pictures. The oldest daughter, Alison, 16, is played by Miss Menges, a former television and magazine model who is a newcomer to acting. The middle girl, Penny, 9, is portrayed by red-haired freckled Susan Neher as the family tomboy. She was a featured player on "The Accidental Family" television series and has made many television guest appearances. The Endicott "baby" is 6- year-old Mary Jane, nicknamed Pokey, played by Melanie Fullerton. She is a blue-eyed strawberry blonde, cuddly and engagingly frank. Little Melanie has modeled and played a guest role on "High Chaparral." To Rome With Love" was created by Joan O'Brien. Its executive producer is Don Federson and the producer is Edmund Hartmann, who were in similar capacities for the "Family Affair" and "My Three Sons" series on the CBS Television Network.