TYLER Batterham is rare gem.
He's a cheeky little bundle of energy who keeps his single mum Chantelle Davies on her toes.
To look at him today, you'd never know this tiny pocket rocket was on his death bed not so long ago.
The toddler is one of only four children in Australia with the potentially deadly genetic condition malonic aciduria.
Worldwide, about 20 children have the condition which prevents their bodies from breaking down fatty acids into energy.
Untreated the fat builds up into their blood stream, which causes swelling on the brain.
Ms Davies said it was scary and stressful to know her then one-year-old son was facing the fight of his short life.
"He was practically on his death bed," she said of her miracle child. "We were told that he may have permanent brain damage, that he may be a vegetable for the rest of his life."
Ms Davies wants more rare conditions put on the newborn screening program so other families avoid the same trauma.
Tyler is now a happy child who is learning to walk and talk and is not far behind children of his own age.
However, Ms Davies said his health could go backward at any time.
"We don't know whether he'll be ever able to have kids or what he's going to be like in his adulthood or teenage years," she said. "He's on medication daily just to increase his energy because he can't have much fats.
"It's very tough, very stressful (and) straining.
"He doesn't like to eat so I have to try to force him, I distract him to try to get him to eat.
"But it's just the stress, like if he doesn't eat and he vomits one time, we've got to take him straight up to emergency.
"So that's always going through my head."
Ms Davies said it was tough dealing with the isolation.
"We've got no one to talk to or no one to find out any information," she said.
"The doctors barely knew anything; they hadn't seen any cases.
"It's pretty scary.
"I am just lucky that I have such a great support system with all family, and my mum is here every day so she helps me quite a lot."
Ms Davies has been selling Genes for Jeans Day merchandise at Stockland every day this week in the hope that one day rare genetic conditions can be diagnosed and treated early.
Genes for Jeans Day, which raises money to help fund birth defect research, is on Friday.