A rare genetic disorder called Prader-Willi Syndrome (PWS) means his brain never tells him he’s had enough to eat, which coupled with a lower metabolism means the family has had to change the way they look at food.

Friday is PWS Awareness Day and Mrs Kelly is hoping people will take a moment to learn about her son’s condition.

When Tobias was born he was different to other babies. He lacked muscle tone and was like a rag doll.

“He was just very floppy and soft to the touch,” Mrs Kelly said. “I had to learn to hold his neck so he could breathe properly.

The term the doctors used was ‘failure to thrive’ and five weeks after they took blood samples they told Mrs Kelly her son had a genetic disorder.

“Besides being floppy there didn’t seem to be anything wrong with him,” Mrs Kelly said.

“They said he had PWS and that if we had to pick a genetic disorder for him to have this is the one we’d want.”

PWS, a non-inheritable disorder, affects about one in 15,000 people. It’s caused by a problem on the 15^th chromosome and it changes the way the body handles food.

Up until about the age of two, children struggle to gain weight and are delayed in reaching developmental milestones. In Tobias’ case, he had to be fed through a nasal-gastric tube for the first nine months and it wasn’t until he was given growth hormones at 18 months that he started to sit, then crawl, then walk.

However, once the second stage of the disorder kicked in, it was like a switch had been flipped in Tobias’ body.

“He suddenly started to gain weight,” Mrs Kelly said.

“I didn’t do anything different, didn’t change his diet, but he got a real interest in food.

“Within six months he went from really tiny to being a different-looking child.”

Tobias’ brain had stopped regulating his appetite and his metabolism slowed.

According to the NSW PWS Association people with the disorder have “an unrelenting, overwhelming, overriding physiological drive to eat”, which coupled with an inability to feel full after eating, means massive weight gain is a real danger. 

People with PWS need to have their access to food strictly controlled, as the ravenous hunger can drive them to great lengths to eat.

Taking growth hormone helps people with PWS gain some semblance of normalcy, but sadly there’s nothing that can control the hunger.

Mrs Kelly said she wanted to raise awareness so the community would learn to accept children like Tobias, who are otherwise happy and friendly like anyone else.

“He just has that feeling of being hungry all the time and there’s food all around us,” she said.