Justin Hemmes' girlfriend Madeline Holtznagel almost has ...

Justin Hemmes' girlfriend Madeline Holtznagel almost has ...
Justin Hemmes' girlfriend Madeline Holtznagel almost has wardrobe malfunction ...

She's the stunning Aussie model dating pub baron Justin Hemmes. 

And on Tuesday, Madeline Holtznagel proved one of the reasons why she caught the billionaire's eye when she showed off her incredible figure in a plunging gown at a yacht party. 

The 24-year-old looked sensational as she stepped out in one of her favourite frocks, as she joined the likes of Instagram influencers Martha Kalifatidis, Bella Varelis and her sister Simone Holtznagel for the Charlotte Tilbury cruise event on Sydney Harbour. 

Hello sailor! On Tuesday, Justin Hemmes' model girlfriend Madeline Holtznagel (left) almost had a wardrobe malfunction in a VERY daring dress as she joined other models and Instagram influencers wearing barely-there outfits for a yacht party. Pictured with sister Simone Holtznagel

Hello sailor! On Tuesday, Justin Hemmes' model girlfriend Madeline Holtznagel (left) almost had a wardrobe malfunction in a VERY daring dress as she joined other models and Instagram influencers wearing barely-there outfits for a yacht party. Pictured with sister Simone Holtznagel

A braless Madeline narrowly avoided a wardrobe malfunction at the event, with her plunging dress skimming her ample assets. 

Her gown also featured a daring leg split, which put her trim pins on full display. 

Madeline finished her look with a pair of strappy black heels, a quilted Chanel shoulder bag and her blonde locks swept into an elegant low bun. 

Careful! While she looked sensational in the show-stopping look, the blonde bombshell appeared a little uncomfortable as she fumbled around with the neckline, trying to prevent a potential nip slip

Careful! While she looked sensational in the show-stopping look, the blonde bombshell appeared a little uncomfortable as she fumbled around with the neckline, trying to prevent a potential nip slip

Careful! While she looked sensational in the show-stopping look, the blonde bombshell appeared a little uncomfortable as she fumbled around with the neckline, trying to prevent a potential nip slip

Daring! A braless Madeline narrowly avoided a wardrobe malfunction at the event, with her plunging dress skimming her ample assets

Daring! A braless Madeline narrowly avoided a wardrobe malfunction at the event, with her plunging dress skimming her ample assets

Don't move an inch! Her gown also featured a daring leg split which helped put her trim pins on full display

Don't move an inch! Her gown also featured a daring leg split which helped put her trim pins on full display

Hot to trot: She was seen walking onto the yacht with her stunning lookalike sister Simone, 28, who rose to fame on Australia's Next Top Model back in 2011

Hot to trot: She was seen walking onto the yacht with her stunning lookalike sister Simone, 28, who rose to fame on Australia's Next Top Model back in 2011 

Dolled up: Madeline finished her look with a pair of strappy black heels, a quilted Chanel shoulder bag and her blonde locks swept into an elegant low bun

Dolled up: Madeline finished her look with a pair of strappy black heels, a quilted Chanel shoulder bag and her blonde locks swept into an elegant low bun

While she looked sensational in the show-stopping look, the blonde bombshell appeared a little uncomfortable as she fumbled around with the neckline, trying to prevent a potential nip slip. 

She was seen walking onto the yacht with her stunning lookalike sister Simone, 28, who rose to fame on Australia's Next Top Model back in 2011. 

The curvaceous beauty, who has modelled for the likes of Playboy

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