Ben Robinson Addresses *Those* Kate Chastain Baby-Daddy Rumors

Ben Robinson insists he’s not the father of Kate Chastain’s 2-year-old son, Sullivan Cay. But is he open to taking on that role?

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The Below Deck Down Under chef tackled the subject during a red-carpet interview at BravoCon 2025, where he reflected on Kate’s motherhood experience and his desire to be part of that journey.

“Kate is an amazing friend of mine, but I’ll tell you what, maternalism has been good for Kate, I think,” Ben told Entertainment Tonight about his former Below Deck castmate. “I think it’s given her something to chew on — responsibility. I think it’s really grounding her.”

Ben Robinson jokes about adopting Kate Chastain’s toddler son
The UK native then touched on those longstanding rumors that he is Sullivan’s biological dad.

“I’m actually pissed off that it’s not my child,” he quipped, “because I’d like to be a part of that.”

Below Deck Down Under’s Joao Franco chimed in on the topic, recalling a time when Ben “wished” that Sullivan was his son.

“I’m thinking about adopting the child,” Ben joked about the toddler. “I don’t know if [Kate would] be OK with that.”

Kate Chastain denies speculation that Ben Robinson is her son’s dad

Kate Chastain and Ben Robinson at the Unexpected Duos panel during at BravoCon on November 15, 2025 at Caesars Forum in Las Vegas, NV.

Photo: Gabe Ginsberg/Bravo

The baby-daddy rumors began circulating shortly after Kate revealed she was expecting her first child and planned to raise him as a single parent. The former chief stew has never revealed the identity of Sullivan’s biological father, which, of course, has led to online speculation and whispers that Ben was the dad. The theory clearly stemmed from the will-they, won’t-they dynamic between Ben and Kate, who have consistently played coy when pressed about their suspected romance.

Although Kate has poked fun at the Ben-Sullivan rumors, she has made it abundantly clear that the two were not related.

“For the record, the only thing this handsome guy has in common with any chef is the tendency to get emotional around meal times,” she declared via X in May of 2023.

Kate Chastain posts side-by-side photos of baby Ben Robinson & Sullivan

But despite her immediate denial, many fans were unconvinced. Whenever Kate would share a video or photo of her newborn son, the post would invariably receive multiple comments referring to Ben as Sullivan’s father. While it’s safe to assume that many of those messages were sent in jest, Kate refused to let the rumor live on. So, what did she do? She posted side-by-side photos of newborn Sullivan and infant Ben to prove they looked nothing alike.

“It would be great if people would stop commenting and messaging me ‘baby Ben!’…….every single day,” she wrote on X back in June 2023. “For reference this is Ben as a baby on the left next to Sullivan. Clearly not related.”

Although they aren’t coparents, Kate and Ben have remained really good friends throughout the years. See what the former had to say about their dynamic and the “secret” to their longstanding bond.