Hold on a minute, Philly — Rocky ain't dead yet, no matter how many hoaxes say so.

Sylvester Stallone, 71, is "still punching" despite a rumor on social media that the actor recently died following a battle with prostate cancer. As Sly wrote on Instagram Tuesday, he is "happy and healthy," and info to the contrary is, at the moment, just "stupidity."

He later joked about the rumor online, posting a video promising a guide on "how to eat healthy when you're dead." In another post, Stallone said that he felt incredibly healthy "for a dead guy."

The rumor, fact-checking website Snopes reports, originated on Facebook, where a post indicating that Stallone "died early this morning after his battle with prostate cancer" began to go viral this week. The post also included images of Stallone with thinning hair and a sickly demeanor, which come from a scene in Creed II, according to Snopes. The film features Rocky battling cancer. He was diagnosed cancer in Creed.

Stallone's younger brother Frank slammed reports of Sly's death on social media this week, writing that the rumors were "sick" and "demented."

"I don't find any humor in this fake post today on my brothers demise," Frank wrote on Twitter. "It upset my 96 yr old mother so I'm doubly upset. I just can understand what makes these sick minded people tick."

As Frank Farley, professor of psychological studies in education at Temple University puts it, it may come down to, among other reasons, fun. The advent of the Internet and social media, he says, have had a disinhibiting effect on our behavior as a society, meaning that online, people are more apt to do or say things they wouldn't otherwise do or say in real life. As a result, these hoaxes could be a way "to stir the social media pot."

"That is empowerment for some people," Farley says. "They started this, and they know that they did it, and now take a look. It reminds me of arsonists, who sometimes hang out and watch their handiwork."

Celebrities, he adds, could be a focus because with a well-known figure, "you know you're going to get attention." Stallone specifically, however, could be a target because of his history in Hollywood.

After all, Sly has been a well-known figure for upwards of four decades, and has been an action movie star almost exclusively in that time. Now, at 71, he's still doing it with films like the Expendables series, and some may see propagating death hoaxes about him as a way to "cut him down to size."

"He's always been a symbol of vigor," Farley says, and death is one surefire way to end that.

This is not the first time Sly has been the subject of a death hoax online. His longtime celebrity coupled with his slide from the A-list spotlight in recent decades helps contribute to making him a repeated target for death hoaxes. He's also 71, and an unexpected death seems a lot more believable than a 25-year-old star. In fact, it is at least the fourth such hoax killing Stallone in as many years.

Previously, in Sept. 2016, another Facebook rumor began to spread that Stallone had died, though it didn't provide a cause of death. Instead, the post, which originated from a misinformation website that has produced similar hoaxes about celebrities like Jim Carrey and Angelina Jolie, presented Stallone's death as breaking news.

To seal the deal that time, the hoax included a CNN chyron and a photo of a body bag being wheeled out of a home in Los Angeles County. The photo, it turns out, comes from the night Sage Stallone, Stallone's oldest son, died in July 2012 at age 36. According to fan site Total Rocky, that posting led only to a story about Sage's death.

Shortly after that hoax in 2016, Stallone posted a photo of himself in Mexico with Carlos Slim, a philanthropist and Forbes richest person in the world from 2010 to 2013 proving that reports of his death were grossly exaggerated.

The internet also killed Stallone in August 2014, when fake news website Media Fetcher produced an article reporting that Sly died in a car accident in Queensland, Australia. The initial report noted that "alcohol and drugs do not appear the have been a factor" in the accident.

Prior to that, there was a rumor in June 2014 that Stallone had died in a snowboarding accident in Zermatt, Switzerland. That report came from Global Associated News, a known hoax outlet that reported Stallone died after hitting a tree while snowboarding. That report also noted that "drugs and alcohol do not appear to have played a part" in Stallone's fake death that time either.

For both of those rumors, Sly was on tour overseas to promote The Expendables 3. Due to near-constant press appearances at the time, neither hoax gained much traction online.

These days, rather than dying of prostate cancer as reported on social media, Sly is working on Creed II, which is scheduled to start filming in Philadelphia next month. The film brings back Michael B. Jordan as Adonis Creed, along with Stallone as Rocky and Lundgren as Rocky IV's Ivan Drago.

As Stallone wrote in an Instagram post after disproving the death hoax, "it's so great to be back from the dead."