Why Simpsons' Smithers finally came out as gay

A scene from the hit TV show The Simpsons.

The Simpsons' Waylon Smithers Jr has come out as gay after 27 years in the closet, thanks to the son of one of the show's writers.

Rob LaZebnik, who is also a co-executive producer on the long-running animated series, has a 21-year-old son named Johnny, who is gay.

"I thought 'What better way to tell my son I love him than to write a cartoon about it?"' the 53-year-old told The New York Post.

Johnny added: "The revelation that my father loves me is not much of a revelation, thankfully. He's unbelievably accepting."

He went on to reveal that his father, who is straight, asks him for advice on gay issues.

The younger LaZebnik revealed: "He once sent me an email, and the header was just, 'How does Grindr work?"'

Gay social network dating app Grindr made its way into the episode, which is titled The Burns Cage.

Broadcast on April 3 in the US, the storyline sees Homer on a mission to find Smithers a boyfriend.

Mr Burns, Smithers' long-time object of affection, leaves his underling devastated by not showing an interest.

Homer turns matchmaker, but he is not completely altruistic - the Springfield resident has an ulterior motive.

Star Trek actor George Takei, who is openly gay, also makes a guest appearance as himself.

Smithers, voiced by comedian Harry Shearer, resists Homer's efforts at first.

"Oh, Mr Smithers. Come in, come in, come in," Homer says at a gathering.

"Can I get you a Tom Collins?" he asks Smithers, pushing forward a young man instead of the gin-based cocktail.

"Hmm, I see what's going on here," Smithers replies. "Fix up your boss so he won't be so hard on you. Well, nice try."

Although Smithers has hinted at his sexuality in past episodes, this is the first time the nuclear plant workers have openly talked about it.

- PAA