NEW YORK – Ay, caramba!

“The Simpsons” turns 30 in 2019, which Fox is commemorating with a slew of events and specials that began with last weekend's 30-episode marathon of beloved episodes on FXX.

The celebration continued Monday at the Empire State Building, which welcomed voice actors Nancy Cartwright (Bart Simpson) and Pamela Hayden (Milhouse Van Houten), writer Stephanie Gillis and executive producer Mike Scully as the New York landmark was lit up in yellow.

Sunday (8 EST/PST), Fox will re-air the show’s first full-length episode, holiday special “Simpsons Roasting on an Open Fire,” which premiered on Dec. 17, 1989, following three seasons of animated shorts on “The Tracey Ullman Show.” ("The SImpsons" began a weekly run a month later).

The episode centers on Homer Simpson (Dan Castellaneta), who learns that he isn’t getting a Christmas bonus at work and has no money for gifts for his family. Making matters worse, Bart gets a tattoo that Marge (Julie Kavner) demands he have removed, thus wasting money that she had set aside for presents. So in true bumbling fashion, Homer goes to extremes trying to scrounge up cash for his family: taking a short-lived job as a mall Santa and even placing bets on a greyhound race, where he rescues and adopts Santa’s Little Helper, the family dog.

The episode ends on a heartwarming note, as the Simpsons sing "Rudolph the Red-Nosed Reindeer" around the piano and Marge calls the pooch “the best gift of all — something to share our love and fight prowlers.”

“It was so sweet,” Hayden says of the special, after posing for photos atop the Empire State Building. “I think anybody can relate to that: (Homer) didn’t have money for Christmas and he was the low man on the totem pole. … But it turned into a good thing for the dog and for the people.”

“I think people were surprised by the amount of heart in the episode,” adds Scully, who joined "Simpsons" in 1993. “They didn’t know what to expect from a 30-minute cartoon and assumed it was going to be all jokes. But I have to give credit to (writers) Jim Brooks, Sam Simon and Matt Groening, because that was kind of the mandate for the show: to write them like real people.”