The $260 stretch jersey top is still available on Higgins’ website, with the designer having stitched up extra pieces, just in case. “You have to rely on the fans finding you because the celebrities don’t always tag the label in their Instagram posts.”

The sales spike for the “Crush” top is not the career-defining moment that Issa designer Daniella Helayel received when Kate Middleton wore her blue wrap dress at the announcement of her engagement to Prince William in 2010 or the headlines Dion Lee made when Taylor Swift wore his corset top to the Super Bowl in February.

That could be a blessing in disguise for Higgins, who has just moved his design studio out of his living room and into a store in Sydney’s Chinatown, opening on Thursday. Issa was not prepared for the Kate-effect and collapsed in 2015. Three months after wearing Swift wore the Dion Lee top, the business entered voluntary administration.

“I think celebrities do an impressive job at assisting brands to have a much wider reach because they have so many eyes on them, but much more work goes into creating a business that will withstand the ever-evolving landscape of this industry,” says Emily Crockford, design manager at the Melbourne footwear brand Alias Mae.

Sandals from Alias Mae have ended up on the feet of reality star, model and influencer Kendall Jenner. Brands will pay Jenner $1.29 million for a post on her social media, according to Vogue, but commercial results vary.

“Yes they help but no, there is so much that goes on behind the scenes to make a brand set for life,” says Crockford, who gained exposure by gifting Jenner product rather than emptying the Alias Mae bank account.

“We have found it’s of the highest importance to only work with celebrities that align with the brand and our customers’ demographic. When you get that right we find it does convert directly to sales, plus is it amazing for your brand awareness and identity.”

Melbourne publicist Clemence Harvey has helped Australian labels work with Kim Kardashian and Paris Hilton on promotional trips to Australia and agrees that a perfect brand fit goes beyond a dress or shoe in the correct size.

“It’s important that the ethics and integrity of the celebrity and the brand are aligned,” Harvey says. “In most cases the celebrities team already have a clear idea of how they want to look and be portrayed.”

Not that Harvey has ever had a label say no to dressing a visiting celebrity because of a conflict in values.

“Are you kidding? Never. The exposure is too good to say no to,” Higgins says.

With orders still coming in, Higgins predicts the Katy-effect won’t match the impact singer Troye Sivan has on sales when photographed in his designs.

Higgins explains: “He’s probably more aligned with my customer base, and he’s very generous with tagging us in his posts.”

If Perry’s stylist calls again, however, Higgins will be racing back to his sewing machine.

“Katy Perry’s amazing,” he says. “I got together with my friends to watch her perform on television. I never knew there was a pre-game show before this happened?”

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