William Bayliss, who lives in Victoria with parents Melissa and Beren, was born with hypoplastic left heart syndrome, which means the left side of his heart didn’t develop properly while in the womb.
The syndrome places enormous pressure on the right ventricle to pump oxygen to his entire body. The cause is unknown.
The active little boy who loves the footy spent most of his first year of life in hospital in Melbourne, where he met his best friend Kye, who also has half a heart.
“Together they make a whole heart,” Kye’s mum Lisa Maree Saygun told Yahoo News Australia.
William has undergone multiple surgeries to allow oxygen to circulate around his body better, but the most recent - which was supposed to take him into early adulthood - has failed.
The four-year-old’s body didn’t react well and he formed blood clots in his liver and neck. Doctors were forced to reverse the procedure.
One week later, he suffered a stroke.
“It was quite traumatic,” his mum Melissa told Yahoo News Australia, adding that she had been in the room at the time.
Boy has only one request for Santa - a new heart
William has since developed some new arrhythmia issues with his heart so he will remain in hospital for Christmas as his family stays at the Ronald McDonald House next door.
He has just one request to Santa this year - a new heart.
The next main option for treatment is a heart transplant, Melissa said.
William is expected to be in the hospital for the next few weeks and then she will bring him home, where they will regroup and let him recover further.
“He will do well for a littler while and they’ll need to push him onto the transplant list,” the mum said.
Doctors are hesitant to perform heart transplants on children until they are 11, when they can receive an adult heart, Ms Saygun said.
William’s oxygen levels are now sitting around 80 per cent, but “will slowly decline as he grows because there will be more pressure on the heart to pump oxygen to a bigger body,” she said.
Brave little boy delights doctors by singing songs
William, who often talks to his friend Kye about their “special hearts”, is incredibly resilient, Melissa said, adding that he often delights doctors and nursing staff by singing Elton John at the top of his lungs.
“They [he and Kye] send each other videos and it’s good for him to see another boy who has the same condition - they made that connection at such a young age,” Melissa said.
Lisa has created a GoFundMe for the Bayliss family to help them pay for rehab and raising their other children while both being unable to work.
“We have received so much support from a lot of people - whether it was mowing the lawn or dropping off food,” she said.
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