A Mitcham mum has spoken about the heartbreak of losing her seven-year-old son in the hope of spreading awareness about genetic disorders.

Natalie McDougall's son Louie was born with the rare, life limiting, genetic disorder SMARD, which affects all muscles in the body.

It causes infants to lose voluntary muscular functions, such as breathing and swallowing.

Natalie said that while he lived a hard life, she and her partner tried to make it as good as possible.

"When he was good he felt really good," Natalie told the Wimbledon Times.

"But when things were bad, they was really bad."

Louie's lungs collapsed aged eight months. His diaphragm was paralysed and since then he has been ventilated – firstly for seven months in hospital, then by using a ventilator the size of a lunchbox at home.

But he sadly died in May this year.

"About six weeks before he passed away we bought him a double medical bed, the kind that go up and down, because he used to be so uncomfortable," Natalie added.

"We weren't able to have it for very long, but it was nice for him while it lasted.

"He was a very chilled out little boy who was always smiling.

"He loved watching Disney films and we managed to take him to Disneyland three times. It was hard work but we made sure we got there."

National charity Jeans for Genes raises money for children and families like the McDougalls who are affected by genetic disorders.

Natalie is hoping to raise awareness by sharing her story.

"You feel lost, like you don’t know what to do," she said.

"I was 21 when I had Louie and at that point I never had a clue about his condition.

"I think it's really important to teach people because we all could potentially have something that affects the people we love."