Mum-of-two Kayarna - who is also a self-confessed Kmart addict - loved the idea straight away and started making plans for the unforgettable photoshoot.
And last week (August, 2) the sisters, from Evans Heads, New South Wales, Australia, drove to their favourite Kmart and began taking hilarious maternity snaps all over the store.
Kirby said: “I just did a traditional maternity shoot on the beach for my first pregnancy. It was really lovely, but I wanted to do something different.
“I’ve always been addicted to Kmart. I will go in there with the intention of just getting one thing and come out with a trolley full of things. I love it.
“It’s such a cult and there are huge groups of people, especially mums, who are also Kmart obsessed.
“My sister is the same as me and we go shopping together at Kmart once a week.
“One day we were walking around the store and I jokingly said, ‘why don’t we do a maternity shoot here in Kmart?’ and we both laughed about how funny it would be.
“But then Kayarna sort of looked at me and said we should actually do it. She was really into it. So I just thought ‘well, why not?’
“Now that I’m further along I’m loving my pregnancy bump and it’s the perfect time to do a maternity shoot. So we went into Kmart last week armed with a camera.
“I was so nervous. I almost didn’t want to do it.
“But we went in and spoke to the manager to check it was going to be alright with him first. He said it was fine and had a good laugh.
“We started off slow, and I was just doing some normal maternity poses. But then we realised that nothing about this entire thing was normal, so we just started doing some funny and crazy poses.
“We had other shoppers stare at us and smile. One lady said she loved what we were doing, and she had a good chuckle.
“It was so much fun and really reflects our unique personalities. I will never forget it.
“We might even do another Kmart photoshoot once the baby is born.”
The hilarious maternity photographs have since gone viral with the post racking up thousands of likes and shares on Facebook.
And despite the sisters going to Kmart with the purpose of the photoshoot, they admitted they couldn’t help themselves while in the store and walked out with a trolley full of new things for the baby.
Photographer Kayarna said: “I was totally up for it from the very beginning. I thought it was such a fantastic idea and something to treasure forever.
“I think more people should do crazy things like this. It was so much fun.
“The whole photoshoot took just over an hour and I took around 300 photos.
“Photography is a huge passion of mine and I’ll always do shoots like this for my family and friends. But this was the first time I’d ever done anything in a department store.
“We were just cracking up the whole time, my ribs hurt from laughing so much. The funniest moment was Kirby squatting on the potty, it was so hysterical.
“I can’t wait until my little niece or nephew get older and I can show them the crazy things their mum and aunty did together. I think we’re going to put all the pictures in a scrapbook.
“It’s great to think outside the box. I’d absolutely recommend it.
“We are so close, and it was such a special thing to do together. I’ll never forget it.”
Related: This 75c Kmart hack is going to change your life
Photographer Kayarna said: “I was totally up for it from the very beginning. I thought it was such a fantastic idea and something to treasure forever.
“I think more people should do crazy things like this. It was so much fun.
“The whole photoshoot took just over an hour and I took around 300 photos.
“Photography is a huge passion of mine and I’ll always do shoots like this for my family and friends. But this was the first time I’d ever done anything in a department store.
“We were just cracking up the whole time, my ribs hurt from laughing so much. The funniest moment was Kirby squatting on the potty, it was so hysterical.
“I can’t wait until my little niece or nephew get older and I can show them the crazy things their mum and aunty did together. I think we’re going to put all the pictures in a scrapbook.
“It’s great to think outside the box. I’d absolutely recommend it.
“We are so close, and it was such a special thing to do together. I’ll never forget it.”
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