A Prince Albert family is preparing to say goodbye to their two-week-old baby girl diagnosed with a rare and fatal heart condition.

Catherine Corrine Shannon Lavallee was born Aug. 4. She looks just like any other healthy baby on the outside, but, inside, her immune system is slowly deteriorating.

The infant has right atrial isomerism, also known as Heterotaxy syndrome. It’s a rare heart defect that affects about one in 10,000 newborns.

“It’s unexplainable, to be honest. It’s what’s going through my heart that really bugs me,” said Catherine’s father, Lawrence Lavallee, sitting alongside family in a private room at Saskatoon’s Royal University Hospital on Friday.

Lawrence and his wife Charnelle anxiously awaited the birth of Catherine after a routine ultrasound 26 weeks into pregnancy when doctors pinpointed the condition. The family was forced to travel to Saskatoon for their baby’s delivery, where the proper medical care could be provided.

“It started from the doctors saying she wouldn’t even make it through birth,” Lawrence said. “She was born and she proved that wrong. At three days old, they said that she would slowly start to shut down. Now she’s 14 days old today (Friday) and she’s proven all of their predictions wrong.”

Doctors told the family surgery for Catherine will not be an option. The family was told all they can do is keep baby Catherine comfortable until she passes.

The Lavallees — Lawrence, Charnelle and Catherine’s brothers Lawrence Jr. and Cashton — say they are devastated by the news. It reminds the parents of a similar incident in 2011 when they lost their 21-day-old son, Liam, to sudden infant death syndrome.

“It’s tough,” Lawrence said. “I have to be here to and be the anchor for my wife and also my two other children, so it’s tough to even explain or elaborate on what’s going on. It’s a devastating feeling.”

A GoFundMe page has been set up to help support the Lavallee family, who has been staying in a Saskatoon hotel for the past two weeks. More than $4,000 has been raised in just 10 days. The money will go towards hospital expense, food and funeral expenses if Catherine does not survive.

“We hope for the best,” said Lawrence. “I believe miracles do happen and I hope she is one of them.”