The quiet, empty room is not an easy sight for parents Kristy and Justin to bear, but they can't complain.

Theirs is a miracle baby.

Kody was born on January 27, five weeks premature, with part of his small intestine outside his body.

Since then, he has been unable to leave Sydney Children's Hospital.

The condition - gastroschisis - limits blood flow to an organ, so it doesn't develop. Kody's large intestine is also very small.

Hours after he was born at Wollongong Hospital he was flown to Randwick, where doctors were forced to remove almost all of his small intestine.

What remained, his parents were told at the time, was not enough for him to survive.

"They cut around as less an amount as they could, but they ended up leaving him with 27cm of small intestine," Mr Tobler said.

"We were told a baby can't live on 27cm. He'd be lucky to last 24 hours, so spend as much time as possible with him. It was hell."

His progress depended on how well he would take to feeding, but Kody took the challenge in his stride.

Almost six months on, he has taken with gusto to a life-saving diet of liquified sugar, fat and protein.

Though he will likely remain reliant on a tube to feed for many years, if not the rest of his life, "Tough Tobler" has thrilled his parents and surprised doctors with his progress.

"I'm over the moon," Mr Tobler said. "We never thought he'd gain so many kilos - he's up to seven kilos."

Kody's gastroenterologist, Associate Professor Andrew Day, said about one in every 6000 babies is born with gastroschisis.

His progress is considered all the more remarkable because he has no ileocecal valve - the valve that should join his small and large intestines.

"If you don't have the valve you usually need 50cm to get full feeding," Prof Day said.

"Generally we had to be cautious with all these things stacking against a little body. We don't know what the future holds ..."

The Toblers hope to establish a foundation in Kody's name to raise awareness of gastro conditions.

And they want him to sleep in his own room - if only for one night - before his first birthday.

"We've got a whole bedroom set up for him but we've never used a thing," Mr Tobler said. "We'd love him to be at home."