Meghan Markle's dress designer reveals how he was subtly told about her baby bump

Meghan Markle's dress designer is opening up about how he learned of the royal baby news!

In a press release, Don O'Neill, the creative director of Theia, shared what it was like dressing Markle -- who's "long been a source of inspiration" -- including the necessary last-minute adjustments. Markle wore the stunning ivory gown to a reception and dinner hosted by His Majesty King Tupou VI and Queen Nanasipau'u on day 10 of her Australian Royal Tour with Prince Harry.

"When her stylist reached out to inquire if I could make a dress for her Australian press tour, I stopped everything we were doing -- my bridal show was just a week away -- and immediately went to work on Her Royal Highness’s gown," O'Neill said of the ivory crepe column gown with a jewel neck, side slit and flanged shoulders that featured hand-embroidered appliques of crystals and micro glass beads. Markle paired the bridal-like look with a black clutch and shoes, as well as the ring her husband gifted her following their wedding, an aquamarine beauty that belonged to his late mother, Princess Diana.

"We completed the gown in two days, shipped it out and received confirmation that The Duchess LOVED it, but with one caveat," O'Neill continued. "We needed to remake it with extra seam allowance."

Though O'Neill could easily infer what that means, he knew to keep the exciting news under wraps.

"We knew immediately why this extra allowance was required, but mum’s the word, and with less than one week to my bridal show, all hands were on deck once more," O'Neill recalled. "We remade the gown and I literally had to run down Broadway that Friday night to catch the UPS truck, making it with just two minutes to spare!"

O'Neill went on to say that he was "sooo excited" to dress the Duchess of Sussex, calling the experience "an exciting whirlwind collaboration."

"Her classic, effortless and chic style coupled with all the excitement leading up to her wedding earlier this year inspired my Spring 2019 bridal collection, which I showed in April," O'Neill revealed. "... Her Royal Highness is a truly beautiful inspiring woman, a bright shining light in this world and we at Theia are truly honored to be part of The Royal Tour of Australia, Fiji, the Kingdom of Tonga and New Zealand."

The gown will soon be available for pre-order for $995.

The expectant parents will spend Thursday and part of Friday in Tonga before returning to Australia to continue their royal tour. Their trip will conclude in New Zealand on Oct. 31.

See some of Meghan's other best looks below!