Sharing a classy picture of some champagne bottles, a few candles and a gorgeous flower arrangement, Pia captioned the post "90 days", suggesting she was celebrating some form of anniversary.
The mystery of the milestone was soon answered by Pia's friend Nina who wrote in the comments: "Congratulations Mr. & Mrs. PPW 😘".
What's more, according to the Herald Sun, Pia's now-husband Patrick, 56, was spotted donning a gold wedding band during dinner with the 37-year-old while the couple were in Malibu.
Pia and Patrick announced they were engaged in November last year. The model informed her fans that Patrick had popped the question via an Instagram post.
"PW²" Pia wrote underneath a photo of two wine glasses along with quite the diamond on her left finger.
The giant ring is estimated to be worth up to AU$1.9 million.
“From Pia Miller's celebratory Instagram post, her ring looks like a 10 carat to 12-carat solitaire oval diamond, set in a platinum band," 77 Diamonds managing director Tobias Kormind told the Daily Mail back in November last year, "which would be priced at between US$800,000 (AU$1.10million) to US$1.4million (AU$1.9million)."
Considering Patrick is the CEO of Hollywood talent agency WME (who represents the likes of Matt Damon) and is estimated to be worth AU$630 million, we're sure the ring didn't make too much of a dent in the 55-year-old's wallet.
Congratulations to Pia and Patrick!
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