Richard Dawson's 1980 birthday episode, on which his son Mark and his daughter-in-law (and the show's producer) Cathy Hughart-Dawson surprised him with a cake. Later, son Gary Dawson surprised him with a visit, which brought him to tears. Dawson ended up bringing on producer Howard Felsher, whom he infamously never got along with, and introducing him to the audience. The whole event took so much time the rules were modified: both families played two survey questions; whoever was in the lead at the end got to play a game of Fast Money; the second family played a different Fast Money game, and both families returned the following Monday.
Richard Dawson gave a long, impassioned speech on the ABC Grand Finale in 1985, thanking the staff and viewers while visibly on the brink of crying. After it, the credits ran without the theme song, and the show ended with announcer Gene Wood saying "Thank you, Richard, thank you, America."
Normally whenever a host brings on a relative, usually their children. Possible subversion of this is when Ray Combs brought on his son in one particular Halloween episode; the two dressed up as Batman and Robin. Moments that play it straight, however, are when Combs came on with his sister Connie Combs-Riggs, Richard Dawson brought on his wife Gretchen and daughter Shannon (in 1994; one episode also saw him bring on his grandchildren), and a couple of episodes where John O'Hurley brought out his wife and then-toddler age son.
When Richard Dawson first walked out onto the new Feud set on his 1994 return episode, the audience gave him a 27-second standing ovation that almost drove Dawson to tears. The audience continued giving him standing ovations for more or less the entire rest of the season, though they weren't nearly as long.
September 16, 2002: On the first episode that Richard Karn hosted, the audience gives him a standing ovation. Karn says, "You've made me feel right at home."