Anaheim, California CNN Business  — 

Nala the cat, a Siamese and tabby mix, is slightly cross-eyed with gray and white fur. She likes being petted but isn’t a fan of being held. She was rescued from an animal shelter and really loves men with beards.

She also happens to have more than 4.1 million followers on Instagram, making her the most followed cat on the photo-sharing app.

Her owners, Varisiri “Pookie” Methachittiphan and Shannon Ellis, also have five other cats and one dog running around their home – all of whom are internet famous, including White Coffee Cat, Luna Rose, Stella and Steve, Spencer, and Apollo. Each have between 17,000 and 1.9 million followers on Instagram.

Nala the Instagram famous cat.

Animals have long been popular online, cats in particular, and having especially photogenic pets has some led people like Methachittiphan and Ellis to a lucrative full-time career.

“The hardest part is that you never really have a day off. It’s 24/7,” Methachittiphan told CNN Business at VidCon, the annual conference for online video creators in Anaheim, California, last week. “You need to take some time for yourself, too.”

In addition to running Instagram accounts for all seven pets, they sell Nala-themed merchandise such as shirts, beanies and pet toys, produce a Facebook Watch show about Nala and work on sponsored content deals with brands on Instagram that start at $8,000 for each post.

For Nala’s Instagram account, they keep it pretty simple. She’s pictured in minimally-edited photos making funny faces, sticking her tongue out, playing with boxes or cuddling with her famous siblings. For some photos, they dress her up in costumes such as a space suit or with accessories on her head like crowns, headbands and hats.

Methachittiphan adopted Nala in 2010 in Los Angeles when she was a master’s student and made an Instagram account for her two years later when the service started taking off.

“It really happened by accident,” she said. “By the second week, Nala had 500 followers, and by the fourth month, she had reached almost 50,000. At the time, I was like, ‘Maybe we have something special here.’”

Methachittiphan took the cat’s burgeoning fame very seriously. In the early days, she experimented with hashtags and finding the optimal time to post on Instagram to keep growing Nala’s following. When she was featured on Instagram’s “Popular” page, now called Explore, Methachittiphan began setting an alarm for 5 a.m. to post photos and increase Nala’s chances of being chosen again to help increase her exposure.

Brands soon started reaching out about sponsored content deals with Nala. That’s when Methachittiphan decided to turn the cat’s Instagram following into a career.

Ellis, who had an Etsy store at the time, reached out to Methachittiphan to send Nala a cat bow tie when she had about 75,000 fans. When Nala hit a million followers, Ellis reached out again to congratulate Methachittiphan. They struck a deal for bow ties for Nala’s online store.

When Ellis delivered the products in person, the two hit it off. They’ve been married for four years and adopted two kids.

“Nala brought us together,” Ellis said.

Nala's owners also have five other cats and one dog, including Luna Rose and White Coffee Cat, pictured here.

Their main source of revenue comes from sponsored deals with brands, including Google (GOOG), Lyft (LYFT), the ASPCA, cat litter maker Fresh Step and a CBD company. Methachittiphan and Ellis declined to say how much they earn annually.

Nala also makes appearances at other festivals beyond VidCon, including CatCon, a convention in Pasadena, California, for cat lovers, and MeowFest, a gathering in Canada that raises money for nonprofits like cat shelters, in addition to other meet and greet events for her fans.

“I think she knows she’s famous,” Ellis said of Nala. “People cry [when they meet her].”

Some fans travel from far away countries, such as Japan, and buy two meet-and-greet passes, she said. Others stock up on merchandise and order even more when they get home.

“We feel overwhelmed,” Ellis said. “Those kinds of fans, we try to know who they are and like go to dinner with them.”

Although they sometimes post photos of their seven pets together (they all get along overall), they have distinct audiences. In addition to sponsored content deals, they use their accounts to raise awareness about animal hunger, fostering pets, adopting animals from shelters and educating people about proper pet parenting. Nala has the biggest career, but the others also partake in sponsored content deals and some make local appearances at local pet stores and events.

Nala has teamed up with other celebrity pets along the way, too. She worked on a multi-year partnership with Grumpy Cat, the internet sensation who died earlier this year. Grumpy Cat landed deals with pet food companies, sold merchandise, starred in a Lifetime movie and even had her own Madame Tussauds wax figure. The cat’s owner has never disclosed Grumpy’s worth but denied a report that she earned $100 million.

That brings up a hard question for people who build their business around their Instagram famous pets: What do you do when they die?

“That is the reality. We think about it often,” said Ellis, who said the pair’s focus is on how to continue helping animals after both they and Nala are gone.

“We know that we have to build something that is sustainable, that lives on its own. That thing will be Nala’s legacy,” she said.