- Was named Patrick because he was born on St. Patrick's Day.
- Became a certified scuba diver as a teen.
- Trained to be an actor in college and was hired as an artist-in-residence upon graduation; appeared with symphonies, operas, ballet companies; taught mime and movement classes.
- Performed for a season with the Old Globe Shakespeare Company in San Diego.
- First TV series as a regular was Man from Atlantis in 1977.
- Big break came when he was cast as Bobby Ewing on Dallas in 1978; he directed 30 episodes of the series.
- Had a hit single in Europe with "Together We're Strong," a duet with French singer Mireille Mathieu.
- Appeared on popular sitcom Step by Step beginning in 1991 and directed 49 of the show's episodes.
- Appeared as Stephen Logan on The Bold and the Beautiful.
- Married wife Carlyn in a Buddhist temple.
- Both sons are both involved in the performing arts: Padraic Duffy is a playwright, and brother Connor is an actor, writer and producer.
- Nephew is Cy Young-winning pitcher Barry Zito.
- Padraic Duffy — Son
- Carlyn Duffy — Wife
- Joanne Hunt — Sister
- Terrence Duffy — Father
- Connor Duffy — Son
- Marie Duffy — Mother
- Barry Zito — Nephew
- University of Washington, Seattle, WA (BA in Drama, 1971)
Season 4, Episode 6
- Birth Name: Patrick G. Duffy
- Birth Place: Townsend, MT
- Birthday: March 17, 1949, Pisces
- Profession: Actor, Director