THIS is the stunning grandmother who is competing against 18-year-olds in a national beauty competition.

Gina Stewart hopes to be crowned Miss Maxim Australia and boasts the only plastic surgery she's had is her breast implants.

Glasgow Times:

Gina Stewart (Credit: Instagram)

She's already through to the semi-finals and she's preparing to go all the way to the top - despite having four children and a grandchild.

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The 47-year-old has racked up 40,000 followers on Instagram.

But her biggest passion is spending time with her family - including two daughters and two sons, aged 27, 25, 23 and four as well as her 10-month-old granddaughter.

Speaking of her “secret” to ageing gracefully, she told the Daily Mail Australia: “The only cosmetic procedure I had was my breasts 10 years ago.

Glasgow Times:

Gina is competing in the Maxin contest

“I don’t use Botox or fillers as I believe in ageing gracefully.

“But seriously, there’s no secret. I think everyone is beautiful. I’m not doing this for attention as I hate it. I’m just trying to make a difference to inspire women not to rip each other apart.”

Glasgow Times:

Gina is a mum of four

If she wins, Gina plans to donate the £5,471 (AU$10,000) prize money to help her friend of 30-years who has recently had a stroke.

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