LOS ANGELES - The night before the Rob & Chyna baby special premiered on E! on Dec. 18, Rob Kardashian announced to his 8.2 million Instagram followers that his fiancee and mother of their month-old daughter had abruptly left him and taken the baby with her.
A few days later, Kardashian replaced those posts with various images of holiday-themed socks from his company. He explained in another entry that he'd been "in an emotional bad place and did some things that embarrassed myself and my family" in the days before. He apologized to fiancee Blac Chyna, said he was "seeking help" for his "flaws/issues," and asked his fans to "please pray for me."
The drama continues to unfold across several media platforms. The couple's reality show has been renewed for a second season, and, according to Kardashian family tradition, social media is where future plot points are born.
The Kardashians are the reality-TV experts of cross-platform storytelling, said Katie Walsh, a doctoral student at the University of Southern California's Annenberg School for Communication and Journalism.
"Rob and Chyna have a TV show, and you can continue watching it on social media," she said. "The other aspect of social media that makes it so important is that it's participatory. . . . Everybody has access to Instagram, Snapchat, Twitter, and then you can actually participate in the story line of the show by making comments on their Instagram."
The Kardashians also are champions of using social media for marketing, said David Schwab, head of celebrity strategy firm Octagon First Call.
"There is nobody like them in the States that has a socialite social footprint and therefore have been able to cross-promote everything they do, from shows to products to anything they want to help a sister or niece or godkid out with," he said.
Rob Kardashian may have kept a lower profile than his sisters in the past, but more interest in his personal life means more potential viewers for his reality show. The first season of Rob & Chyna, which launched in September, tracked the newly engaged couple's preparations for the birth of their first child together. Daughter Dream was born Nov. 10.
E! would not provide weekly ratings data for the show, but it was popular enough to be renewed. The network said last week a second season of Rob & Chyna was in the works. No premiere date has been announced.
Kardashian has a long way to go to catch up with the social-media reach of his five sisters, each of whom has more than 50 million Instagram followers. Kim Kardashian West, who has been on a social-media blackout since being robbed at gunpoint in Paris in October, has 89 million followers on Instagram and 49 million on Twitter.
Chyna, who has been using her Instagram feed to promote a variety of products, has 10 million followers on the photo-sharing site.
Having a TV show gives the Kardashians "a mark of legitimacy" that helps fuel their marketing power, Walsh said.
"It's all little bits of advertising that they're spreading around to all these different platforms," she said. "So they're selling their followers' attention to advertisers - whether its flat-tummy tea or teeth whitening, or whatever they're selling - or they're promoting their own businesses and the stuff that they sell: Khloe has jeans, Kylie has makeup, Rob has socks. But they have to give some part of themselves away for people to pay attention to it."
Sharing details from their personal lives and relationship dramas has become part of the family business, Schwab said.
"The personal revelations just add to the fascination and gossip around them," he said. "It's a circular machine."