Tamworth baby Molly Allen had heart surgery at six months old

Her mother Sarah Allen was 20 weeks pregnant when a scan identified the defect in her unborn baby, which consisted of a hole in the heart and a narrowing of the lung artery which often leads to low blood oxygen.

It is enough to make any parent worried with grief, but Mrs Allen and her husband Ben Allen were reassured by one of the country's best paediatric cardiologists Dr Jascha Kehr from John Hunter Hospital in Newcastle.

"When he first saw me, he did his little drawings; two little pictures of what the heart should look like and what the heart with a hole in it looks like," Mrs Allen said.

"They [health staff] just said, 'don't stress because if you're stressed the baby stresses'."

Little Molly was born on October 31, 2022, and for the first six months of her life she had multiple scans and tests before being admitted to Sydney's Westmead hospital on April 14.

"They had to break her chest bones and she was in surgery for probably four hours," Mrs Allen said.

"They fixed the hole, and one of the valves was smaller than it should have been so they removed it, because it was like a cabbage and it hadn't been working for the first five and a half months of her life.

"So now she just may have to have surgery when she's a teenager."

Molly "bounced back" so quickly that the family only needed to stay in Sydney for about a week before they were back home in Tamworth.

Mrs Allen said she was one of "the lucky ones" because Molly was not born with the blue tinge that most babies with ToF usually have when they arrive in the world due to low oxygen levels in the blood.

"You wouldn't even know that she's had surgery. She's such a bubbly, healthy child. She eats anything you give her," Mrs Allen said.

"And she thrives on attention and food and family and all the people who love and care for her."

Molly's paediatric cardiologist, Dr Kehr, said even though ToF can be carried through genetics or due to other factors such as diabetes, there is often no known cause for it.

He said Molly will always need to see a cardiologist throughout her life to prevent any complications, such as heart arrhythmia or heart failure.

"Anyone who's had heart surgery early on in life has these risk factors, so the question is about ongoing monitoring," Dr Kehr said.

"But most people with Tetralogy Of Fallot, once it's been repaired, do really well."

Dr Kehr said it is "unfathomably hard what the parents go through".

"I don't think any one of us can understand how hard it really is to hand over your child for cardiac surgery unless you have to go through it yourself."

The paediatric cardiologist said every year he sees about four or five babies in the Hunter New England region born with ToF.

Mrs and Mr Allen will be doing a four-kilometre walk in Tamworth with Molly, her five-year-old brother James and about 22 of their closest friends and family on Sunday, October 15.

The walk, which coincides with others throughout the nation, is to raise awareness about ToF and the four young lives the congenital heart defect claims every week in Australia.

The event is being organised by Two Feet and A Heartbeat and people can support the fundraiser by going to the website.

Our journalists work hard to provide local, up-to-date news to the community. This is how you can continue to access our trusted content: