Can you see what's different about this bikini photo?

Allison Yee

In the Instagram world, bikini photos are a dime a dozen.

But when model Sarah Stage posted a shot of her in a skimpy red bikini, there was one big difference that had social media buzzing.

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Showing off her incredible figure as she posed in her swimmers, the 33-year-old brunette was seen standing at the foot of her bed, with her hand resting on her belly.

Sarah's photo has been liked nearly 30,000 times in the few hours it has been up. Photo: Instagram

But it’s not just any old belly. It’s a nine-month pregnant belly

Sarah, who is already mum to James Hunter, is expecting her second child any day now.

Sarah posted this snap of her at 32 weeks, with her son James. Photo: Instagram

“How is she pregnant? Where is the bump?” commented one follower.

“Has a better stomach then me and I'm 0 months pregnant ahah,” added another.

The super fit mum was 24 weeks in this snap. Photo: Instagram

The 33-year-model, who shot to fame as the ‘six pack mum’ during her first pregnancy, revealed last month that she was still exercising twice a week to keep her energy levels up.

Looking much the same as she did with her first baby, Sarah has documented every stage of her second pregnancy – showing off her unbelievable belly, with many mums-to-be praising the inspiring posts.

“I'm pregnant too!! Just loving my new fitness journey while pregnant. You look great girl!!” said one.

“Amazing!! I'm 35 weeks and you have been such a huge inspiration to me!!” wrote another.

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