Pregnant April Love Geary, 22, shows off her baby bump

They announced they were expecting their first child together last month in a series of sweet Instagram snaps.

And April Love Geary, 22, looked as though pregnancy was suiting her down to the ground as she and Robin Thicke, 40, attended the inaugural Gala For The Global Ocean at the Monaco Garnier Opera in Monte Carlo on Thursday night.

The model showed off her beautiful baby bump in a dramatic sheer black gown as she worked her magic on the red carpet at the glittering charity event, which honored Oscar-winning actor Leonardo DiCaprio, 42. 

Bumping along: April Love Geary, 22, and Robin Thicke, 40, attended the inaugural Gala For The Global Ocean at the Monaco Garnier Opera in Monte Carlo on Thursday night

Comprised of see-through net fabric, April’s unusual choice of dress also put her 50s-style underwear on display as she sashayed down the red carpet with her musician boyfriend. 

The pretty brunette wore her long locks scraped back from her face, while accentuating her striking features with winged eyeliner and nude make-up.

Not letting his leading lady down in the sartorial stakes, Blurred Lines hitmaker Robin was suited and booted to perfection in a dapper navy two-piece, black shirt and black bow tie. 

It was a star-studded date night for the couple, and even had the royal seal of approval with Prince Albert II and Princess Charlene of Monaco also in attendance at the gala. 

Mom-to-be: The model showed off her beautiful baby bump in a dramatic sheer black gown as she worked her magic on the red carpet at the glittering charity event

Mom-to-be: The model showed off her beautiful baby bump in a dramatic sheer black gown as she worked her magic on the red carpet at the glittering charity event

Sheer daring! April's unusual choice of dress also put her 50s-style underwear on display as she sashayed down the red carpet with her musician boyfriend

Sheer daring! April’s unusual choice of dress also put her 50s-style underwear on display as she sashayed down the red carpet with her musician boyfriend

Robin and April surprised fans when they revealed they were expecting their first child together last month. 

The pair’s new addition is remarkably set to arrive on what would have been the birthday of Robin’s late father, Alan.

The singer’s father, actor and songwriter Alan Thicke, passed away at the age of 69 in December 2016.

He would have turned 71 on March 1, 2018, adding a special poignancy to the couple’s impending arrival.   

A royally good evening! It was a star-studded date night for the couple, and even had the royal seal of approval with Prince Albert II and Princess Charlene of Monaco also in attendance

A royally good evening! It was a star-studded date night for the couple, and even had the royal seal of approval with Prince Albert II and Princess Charlene of Monaco also in attendance

Star-studded: Robin posed alongside (L-R) Adrien Brody, Olga Kurylenko, Lior Suchard, Prince Albert II of Monaco, Princess Charlene of Monaco and Nelly Furtado

Star-studded: Robin posed alongside (L-R) Adrien Brody, Olga Kurylenko, Lior Suchard, Prince Albert II of Monaco, Princess Charlene of Monaco and Nelly Furtado

April announced the couple’s happy news on August 17 via her Instagram page, writing: ‘Robin and I are very excited to share with you all that we’re having a baby! The due date is March 1st, Alan’s birthday!’   

According to TMZ, the happy couple are expecting a baby girl, a sister for Robin’s son Julian, seven, who is ‘said to be ‘super excited’ to be a big brother. 

The Lost Without You hitmaker shares Julian with his ex wife Paula Patton, 41, who he split from in February 2014 after nine years of marriage. 

The couple had been together for more than two decades before their divorce was finalized in March 2015. 

The former couple were childhood sweethearts; meeting when he was just 14 and she was 15. 

Oh baby! April announced the couple's happy news on August 17 via her Instagram page

Oh baby! April announced the couple’s happy news on August 17 via her Instagram page

Speaking about their shock break-up at the time, Robin dismissed allegations that cheating lead to their demise, insisting there was ‘a long list’ of reasons they couldn’t make it work, though hinted he was solely responsible.

He told radio station Hot 97 in July 2014: ‘[Cheating] is not why we’re apart. We’re apart because we just couldn’t be together anymore for a while. 

‘There’s a hundred different reasons, there isn’t just one. There’s a long list… I changed, and I got a little too selfish, a little too greedy and little too full of myself.’ 

The Blurred Lines hitmaker embarked on a blossoming romance with model April following the break-up, with the couple going public with their romance in May 2015.

Happy: Robin and April's new addition is remarkably set to arrive on what would have been the birthday of Robin's late father, Alan 

Happy: Robin and April’s new addition is remarkably set to arrive on what would have been the birthday of Robin’s late father, Alan 

Family: The Lost Without You hitmaker shares son Julian, seven, (pictured in Hawaii with Robin and April) with his ex wife Paula Patton, 41

Family: The Lost Without You hitmaker shares son Julian, seven, (pictured in Hawaii with Robin and April) with his ex wife Paula Patton, 41

April has previously addressed her 18-year age gap with Robin, writing on her Instagram page: ‘We’re out here LIVING while most of y’all are still bothered by an age gap.’   

Robin has made no secret of wanting to expand his brood; in February, he said: ‘It’s my favorite thing to do in the world. I plan on many more.’ 

The singer and his ex-wife were locked in a bitter legal battle earlier this year.

Actress Patton stated in court documents that she was concerned about the safety of her son in the wake of two incidents last month where he allegedly spoke of being hit by his father.

The two have since agreed to resolve their custodial issues in private. 

Bikini babe: April first revealed her baby bump to her loyal army of Instagram followers in a swimsuit snap from her babymoon in Hawaii last month  

Bikini babe: April first revealed her baby bump to her loyal army of Instagram followers in a swimsuit snap from her babymoon in Hawaii last month  

  

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