Josh Duhamel Is Engaged to Audra Mari: A Timeline of Their Relationship

Audra Mari/Instagram Audra Mari and Josh Duhamel

Josh Duhamel and Audra Mari are headed to the altar.

The Transformers actor, 49, and former Miss World America announced their engagement on Saturday — Mari's 28th birthday — after more than two years of dating.

"It's on!! She found a message in a bottle that washed ashore and said YES!! @audramari," Duhamel captioned a shot of the pair smiling, while he held up a handwritten letter that read, "Audra Diane Mari Will You Marry Me?"

Sharing the same image to her own Instagram account, Mari wrote, "my heart is so happy ... I love you @joshduhamel."

Duhamel and Mari's relationship dates back to 2019. In December of that year, a source told PEOPLE that the actor was "really happy" with Mari, whom he'd begun seeing romantically "seven or eight months" prior.

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The source's comment came amid a holiday party the two attended together that month, at which Duhamel and the model "were basically together all night," an onlooker told PEOPLE at the time.

The couple was later snapped holding hands in Los Angeles in February 2020, and out for a date night at celebrity-loved sushi hotspot Nobu in May of last year.

While the December 2019 bash was not Duhamel and Mari's first time spotted out together, the party took place about two weeks after Duhamel's divorce from ex-wife Fergie was finalized.

Photographer Group/MEGA Josh Duhamel (R) and Audra Mari

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Fergie and Duhamel — who were married for eight years and share son Axl Jack, 8 — announced their split in a joint statement obtained by PEOPLE in September 2017. The former Black Eyed Peas singer, 46, filed for divorce in late May 2019.

"With absolute love and respect we decided to separate as a couple earlier this year," they said, in part, in their 2017 statement. "To give our family the best opportunity to adjust, we wanted to keep this a private matter before sharing it with the public."

The "Fergalicious" singer celebrated Duhamel and Mari in the comment section of her ex's Saturday post announcing their engagement, writing, "Congrats!!!💚💚💚💚💚💚."