Coco Rocha and Close Friend Christian Siriano Talk Headline-Making Pool Moment in ET Interview (Exclusive)

Rocha made headlines as she closed out Siriano's runway show last month by walking into his pool!

Christian Siriano held his runway show in his backyard in Connecticut last month -- but that doesn't mean it flew under the radar. In fact, the show made headlines, as Coco Rocha traded the runway for his swimming pool. 

A month later, the supermodel -- who is seven months pregnant with her third child -- still isn't sure who came up with the idea. "Whose idea was that?" she asked Siriano while interviewing him for ET on Tuesday. "I was in makeup, and then my husband came over and said you were kind of talking..." 

"It was his idea," Siriano said. "I think so... also, I blacked out. I don't remember anything I said. But I also didn't think you would do it." 

"It was a test," Siriano joked -- which Rocha definitely passed. 

The dress weighed more than expected while wet, and Rocha ended up needing an escort on her way out of the pool. The gown took a full week to dry, Siriano said. "I checked it every day," he revealed. "I just hung it and let it dry, and let me tell you, it looks perfect. It really looks like nothing happened." 

The $10,000 dress will be sold "as is," according to the designer -- and probably end up "in a museum one day." 

Siriano is as in-demand as ever, dressing stars like Lizzo, Julianne Morre and Julia Roberts -- but he's still adding more to his plate. The Project Runway mentor -- who says the show won't be back in production until sometime next year due to coronavirus -- is hosting a new digital talk show. So Siriano premieres new episodes every Thursday on Bravo.com. 

"Let me tell you what I do on my show. I am tech support, I'm glam, I literally do it all," Siriano told Rocha. "I reach out, I follow up, I send flowers. The studio is at my house. It's a lot of work!" 

Rocha can relate. The model of three is still runway coaching, even as she prepares to welcome baby No. 3.

"I'm so off balance because how I walk. I kind of teeter back," Rocha joked. "I'm leading by this bump and then my head and my body is just way back there." 

"I don't know if it's cute or not, but I'm just going to keep going with it," she quipped. 

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