Harper refused a trip to Macca's. Hours later, her mum was racing her to hospital to save her life

Katrina's worst nightmare began with the sound of her daughter crying out in the dead of night.

Harper, seven, had woken with a sore leg and called out for her mum but Katrina wasn't worried at first; Harper was an active kid and had played basketball that very day.

"I literally just tucked her back into bed," Katrina told 9honey.

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But when the sun rose, Harper wasn't herself.

Lethargic, feverish and still complaining of leg pain, Katrina started to suspect something was seriously wrong when Harper even refused a trip to Macca's.

"I just had this feeling in my stomach, like 'something's not adding up'," Katrina said.

"Then she started vomiting."

Soon Harper's temperature had hit 40 degrees and she could barely walk.

Have you got a story? Contact reporter Maddison Leach at mleach@nine.com.au

A telehealth doctor urged Katrina to get her to hospital, but when they arrived the emergency department was so busy it was standing room only.

Unwilling to make Harper stand in the crowd for hours, Katrina took her home and resolved to visit their GP first thing in the morning.

At 4am, Harper started spewing up bile. Katrina knew she couldn't wait.

She and husband Craig raced their daughter to Monash Children's Hospital where doctors immediately started running tests.

Although blood tests quickly revealed Harper's infection markers were elevated, nothing seemed amiss on X-rays or ultrasounds.

Whatever was causing her pain was buried deep and no one could say how long it would take to find the cause or treat it.

"When you don't have the answers it becomes really overwhelming, you're running on next to no sleep ... it was emotional and many tears were shed," Katrina said.

"I consciously made this little commitment in my head not to Google. Doctor Google is not going to help."

For the next 36 hours, all she and Craig could do was wait and hope for a breakthrough.

Harper continued to deteriorate and Katrina feared the worst.

"I remember being on the phone to my mum ... and I just said, 'I can't lose her. She's everything to us,'" she said tearfully.

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Finally, Harper was sent for an MRI that uncovered the truth.

It revealed she was suffering from osteomyelitis, a type of bone infection that had taken root in her hip and festered, causing sepsis, a potentially deadly blood infection.

Doctors couldn't explain how the osteomyelitis had started, as the infection could have entered Harper's bloodstream through something as innocent as a scratch.

"They said, you could be trying to search for answers for the rest of your life and you will never have them," Katrina recalled.

"They just don't know."

Learning how sick Harper really was terrifying but she and Craig were relieved to finally have answers – and a treatment plan.

Harper was immediately started on strong IV antibiotics but doctors warned that if she didn't improve soon, surgery might be the only option.

Thankfully, luck was on Harper's side. The antibiotics kicked in quickly and within 24 hours her pain had eased. A day after that, she was up and walking again.

Katrina still can't put into words how relieved she was to see her daughter on the mend.

Then a new problem emerged.

"All she wanted to do was go home. I think every doctor who came into her room she asked, like, 'Can I go home now?'" Katrina said.

"Trying to explain to her that she had to stay there, and we still didn't know if she'd require surgery ... it was hard."

Fortunately, Harper was well enough to start visiting the Starlight Room, where she instantly bonded with the Starlight Captains who helped her forget she would be stuck in hospital for a little longer.

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It also gave her the chance to connect with other children on the ward and showed her that she wasn't alone.

"She saw other young people that had cannulas in their arms or were needing to take medical equipment with them," Katrina said.

"It just normalised our days in there, I suppose. It made her feel like she wasn't different."

After a week in hospital, Harper was sent home with high-dose antibiotics she had to take for another six weeks while her body slowly healed.

She had to take it easy for a few months and the side-effects, which included bouts of vomiting, weren't fun but before long she was back to her "sassy" self.

Now fully recovered, Harper is back to being the active little girl she was before she fell ill and was even named MVP by her basketball team at the end of the season.

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She's also picked up a new passion few kids her age ever consider: advocacy.

The Starlight Captains made a huge impact on Harper when she was in hospital and, with mum's support, she's been fundraising for the charity ever since.

"When you talk to her now she's always saying, 'I want to be a starlight Captain when I grow up,'" Katrina said.

"We're using it as a lesson for her as well, about giving back."

Harper and her family are sharing their story in support of Starlight's annual Tax Appeal, which aims to raise $1.3 million to make hospital a happy place for seriously ill children. Learn more and donate here.

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