"[Mulroney] loves fashion, and she loves cutting-edge fashion, and I think I can see [with] Meghan, that excites her as well," he said. "You know how fashion girls are, you can't let it go, it's a part of who you are! I think Meghan's like that. I think Jessica feeds that."
Zunino doesn't know who Markle chose as her wedding dress designer -- "I'm trying to get it out of Jessica," he confessed -- but he estimates that the gown will cost "at least $100,000 or more."
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"You know, [it will cost] $100,000 to $300,000, because she's going to showcase everyone: herself, her family, his family, the country, our country, Canada. She's representing everything," Zunino said. "I wouldn't be surprised if she picked a Canadian designer, but something that is either her roots or respectful to the country that she's marrying into."
Zunino, who said Markle will likely have 10-15 fittings for her gown, said that Markle shouldn't worry about possibly upstaging her soon-to-be sister-in-law, Kate Middleton, on her wedding day. "Kate was Kate, Meghan's going to be Meghan. Princess Diana was Princess Diana," he expressed. "I think you can already tell the difference in their personalities."
"Meghan's holding back a little bit, but you can see the little sparkle in her eye that she's ready to go a little further," he added. "Kate fits right into the polish of the royal family. She's got it down. So I think at the beginning, you can be a little bit of a wild child."
Zunino describes Markle's style as "unexpected." "I think that Jessica definitely does it, and I think Meghan will do some things that kind of are a little eye-popping -- not in a bad way, just in a, wow, she really is making her mark," he explained, pointing to Markle's engagement photo shoot as an example. "I think she's going to test her surroundings that way, try different things, see the reaction of the world."
As for what type of wedding dress he can see Markle wearing, Zunino says he can definitely see her "pushing the envelope."
"I think she will definitely kind of push the envelope but I think she'll be definitely respectful to the royal family and, you know, to the UK in general," he says. "Nothing will be too exposed. I think she might go a little more form-fitted. She'll still make the grandness of something, you know, embellished sleeves or a big flounce or something for the magnitude of the cathedral, but I think she's going to go a little, you know, sexier in not an obvious way. I think she's gonna redefine princess."
"I just think that she's seeing who has done what, I think everyone recognizes the magnitude of Princess Diana," he continues. "And I think that as long as you're authentic, I think it will work, and I think for her it is authentic. I think maybe it is a little outside the box. She is pushing the envelope, you know, she knows she's got a group of haters after her and she really doesn't care because she's in love and she knows what she likes, and so you can't go wrong."
Zunino, who has dressed Hollywood celebrities like Katy Perry, Angelina Jolie, Sofia Vergara, Beyonce, Julia Roberts and more, also dished on bringing his signature style that the stars love so much to his signature bridal line.
"We do a very tight, French, steamed ruche. A lot of people think, 'Oh, ruching gives you bulk,' and it doesn't when it's done right. It makes you very skinny," he described. "The first thing a bride says to me, 'I'm planning on losing weight,' whether they need to or not... And then all of a sudden, they'll put on a dress, and they're like, 'Oh, my God. I just lost that 10 pounds!'"
"This year, it's a lot of texture [and] dimension. We're kind of getting away from all the nudity, so things aren't quite so sheer," he continued of current bridal trends, adding that with his collection, no matter a bride's budget, "Everybody can have what they want. Everybody can be fashion forward."
At the end of the day, however, Zunino said it's all about what makes a bride feel her best. "Don't let criticism dictate what you wear," he implored. "Try things and see what you feel the best in, and also try everything on... Try it on every now and then, but it may become you."