An 11-month-old baby is in desperate need of a heart transplant, English doctors have told his parents.

Theo Davies is battling to stay alive and doctors tell his parent that, if he doesn't have a heart transplant within the next two weeks, the baby could die, the Daily Mail reported.

Theo was born with hypoplastic left heart syndrome, a condition in which the left side of the heart — including the aorta, aortic valve, left ventricle and mitral valve — is underdeveloped. The defect is not correctable, but some babies can be treated with a series of operations or a heart transplantation, according to the American Heart Association.

Theo has had five operations to stabilize the condition, but a heart transplant is his only chance of survival, according to the report. His parents, Ryan Davies and Rebecca Giles, are desperate for a donor to save little Theo, who has spent the last four months of his short life at Freeman Hospital in Newcastle, England.

"Theo is on a life support machine now and the very maximum someone can stay on that is six weeks," Dr. Richard Kirk, a pediatric cardiologist at Freeman Hospital, told the Daily Mail. "A lot of children die while waiting for a donor and I really hope that Theo finds a new heart in time."

Theo's father, a 22-year-old builder, told the newspaper his son has amazing strength, surviving an operation last week in which his heart stopped for over an hour.

"We were told that he would probably have brain damage because there was no oxygen going to his brain but when they came back with some test results it showed that there was no damage," Davies said. "It just underlines how strong Theo is. He's been through so much in his short life and all he seems to do is fight back."

Click here for more on this story from the Daily Mail.

Click here for more information on hypoplastic left heart syndrome.