“GMA” news anchor Amy Robach and James Middleton posing with marshmallows (Ida Mae Astute/ABC)

Those Middleton siblings — they really know how to leverage fame to do something that sounds way more fun than being a member of the royal family.

James Middleton, 27-year-old brother of Kate and Pippa, mostly shuns the spotlight. That is, until he has a marshmallow business to promote. He runs a company called Boomf, which creates personalized marshmallows with photos. His title is “Wonka-in-chief.” (Yeah, he definitely sounds weird and also like he is probably the coolest Middleton sibling.)

Pippa Middleton (R) and James Middleton (L) at 2014 Wimbledon Championships (Glyn Kirk/AFP/Getty Images)

Theoretically, that’s why he showed up on “Good Morning America” Wednesday. Though just as when Pippa appeared on the “Today” show, “GMA” pounced to make most of the interview about the family members everyone really cares about: Princess Kate, along with 16-month-old Prince George. James was introduced as “the royal brother-in-law. . . brother to the future queen and uncle to the future king,” while his marshmallow business partner sat quietly beside him.

News anchor Amy Robach got right down to it, asking James about what it was like being part of Prince William and Kate’s royal wedding. He echoed Pippa’s “Today” response, that “although billions were watching, it felt like a family wedding.” And yes, his wedding gift to the couple was their puppy, Lupo.

After the wedding chatter, it was onto George — an excuse to show cute footage of the toddler. “I want to be the best uncle possible, like any uncle wants to be. ” James confessed. “I want to be the cool uncle, the fun uncle.” (No, he hasn’t gotten him a Christmas present yet, as we know you were wondering, but he’s mulling ideas.)

Britain’s Catherine, the Duchess of Cambridge, holds her son Prince George. (Phil Noble/Reuters)

“How often do you get to spend time with your sister Kate and your nephew George?” Robach inquired.

“We’re a really close family,” James confirmed. “And actually, we see each other and speak on the phone all the time. . . the odd Sunday lunch, or pop in for coffee or something like that.”

Cut to: Robach and James taking a random walk outside as she grilled him about his future niece or nephew, due next spring. James said his sister is “on the mend” after suffering from acute morning sickness.

“We are hearing that she may come to New York,” Robach said, a bit too eagerly.

“I heard that too. Um — I — I, um, I don’t — I’m not — I don’t really know,” James said, looking a little fearful.

“We would be very excited to host her if she does feel up to it to come,” Robach pushed. She has obviously heard rumors that NBC is on the verge of signing Pippa (party-planning book author, Vanity Fair columnist) as a lifestyle correspondent. Better try to lock that up!

Afterward, James and his business partner, Andy Bell, appeared with the rest of the “GMA” gang — George Stephanopoulos, Lara Spencer — as they showed up with personalized Boomf marshmallows for the crew. (The name “Boomf” originated from that idea that if you taught a marshmallow to speak, that’s the first word it would say.)

Naturally, the topic quickly came back around to James’s royal relatives.

“There are great for kid’s birthday parties, things like that,” Stephanopoulos said, then pivoted: “James, I have to ask, are you making progress on being the cool uncle?”

“Well, I think there’s a long way to go to try and be a cool uncle. I’m just trying to be — yeah, as best as I can, really,” James said. “GMA” quickly used the opportunity to cut away to show video footage of George being adorable.

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