Series creator Brenda Hampton discovered "Happy" the dog on another set and then decided to write her into the show. She was only 7 months old when she did the pilot.
At the start of the series' 10th season this became the longest running family drama on television beating out Little House on the Prairie (1974) and The Waltons (1972), both of which aired for nine seasons.
The longest running TV series on The WB
Before working on the show, the dog "Happy" was a stray that was abused by her former male owner. Even though she was later rescued "Happy" still has a fear of men. Before the taping of every new season Stephen Collins, Barry Watson, and other adult male actors on the show have to spend some time with Happy for her to get used to them being around when doing scenes together.
Stephen Collins (Reverend Eric Camden) was offered the role of Eric Camden two days before the pilot episode was filmed. He never auditioned for the role. The next day he met the entire cast in Aaron Spelling's office and read the script out loud with them. It was then when he accepted the role.