The pregnant royal was spotted in October, whilst on the second day of her royal tour to Australia with husband Prince Harry, wearing an oversized plaid blazer from her friend Serena's eponymous line prompting a rush on the garment which instantly sold-out.
Since that happened, the American tennis legend has instructed her team to create items specifically made for the former 'Suits' star, which she admits have been a lot of fun.
Speaking to Marie Claire magazine, Serena said: "Since that blazer sold out, now we just have special pieces that are specifically made for Meghan and we send those to her. It's been fun creating them."
Serena, 37, was very grateful to Meghan for choosing to wear one of her label's garments and therefore promoting it around the world, but the ex-actress was adamant she chose the blazer because it made her look good.
She added: "We were all just coming out of a photo shoot for the brand when we heard that Meghan wore our line. We had sent stuff to her a while ago, so we were excited to see it. I've known her for years and it's cool to see your friend help you out without even trying. She just wanted to look good and wear a blazer. The next thing you know it's our blazer. I was like 'Meghan, thanks!' And she was like 'Why are you thanking me? We're friends!' "
Fans of the royal have been desperate to get their hands on clothes she's been pictured in, and the duchess has caused websites to crash in what has now been dubbed 'The Meghan effect'.
In October, Meghan caused yet another dress to sell out in every size after wearing a beautiful blue outfit on the second day of her visit to Tonga.