My Three Sons - Season 9 - Eps 16: Chip and Debbie
Chip and his girlfriend announce to a startled Douglas family that they plan to marry and continue high school. Disapproving, Steve visits the girl's parents but they decide not to forbid the marriage but wait for further developments. When Katie becomes ill and Robbie takes her to the doctor, Chip and Debbie are left with the triplets for some hectic hours.
About My Three Sons

Title: My Three Sons
First Air Date: 1960-09-29
Last Air Date: 1972-04-13
Status: Ended
Rating: 6.5/10 (from 33 votes)
Language: EN
Seasons: 12
Total Episodes: 380
Network: CBS
Genres: Comedy, Family
Production Companies: MCA Television, Don Fedderson Productions, Gregg-Don Inc.
Synopsis
A widower and aeronautical engineer named Steven Douglas raises three sons with the help of his father-in-law, and later the boys' great-uncle. An adopted son, a stepdaughter, wives, and another generation of sons join the loving family in later seasons.
Cast

Fred MacMurray
Steve Douglas

Don Grady
Robbie Douglas

Barry Livingston
Ernie Thompson

Stanley Livingston
Chip Douglas

William Demarest
Charley O'Casey

Beverly Garland
Barbara

Tina Cole
Katie

Dawn Lyn
Dodie Harper Douglas