Which Seinfeld episode was the first broadcast episode to feature Jerry's parents?

“The Stake Out” was the first broadcast Seinfeld episode to feature Jerry’s parents, Morty and Helen Seinfeld.

The episode is the second broadcast installment of season one and first aired on NBC on May 31, 1990. Jerry gives up his apartment while his parents visit for a wedding, forcing him to sleep at Kramer’s place. Their visit also supplies advice and complications as Jerry tries to locate Vanessa, a woman he met at a party.

The episode is notable beyond introducing Jerry’s parents. Morty suggests that Jerry stake out Vanessa’s workplace, inspiring the title and one of the series’ early recurring comic situations. George also invents the name Art Vandelay while helping Jerry create a cover story, launching one of the show’s most enduring running gags.

The episode’s production history is slightly complicated because Morty was later recast. Phil Bruns appeared in this broadcast episode, while Barney Martin played Morty in later appearances. Liz Sheridan established Helen Seinfeld in the role.