'Race against time': Block 'villains' reveal heartbreaking family struggle

Instead, they're dealing with tremendous family heartache.

"It's the hardest thing we've ever had to do," Mitch told A Current Affair in an emotion-charged interview.

The couple's grand-daughter Carli is battling a cruel and potentially life-threatening condition known as Dravet syndrome.

It's rare and very serious form of epilepsy which causes painful seizures.

"Every time there's a seizure, there's a risk that part of the brain will die off," Mitch said.

It's devastated their entire family.

Carli's parents Chad and Tamara, from Sydney, have been forced to watch their little girl suffer multiple seizures, including one which lasted close to an hour.

"It's terrifying," Tamara told ACA.

The parents were initially told by doctors that Carli had simply been suffering febrile seizures or that she was having a bad reaction to her immunisations, however dad Chad wasn't convinced.

"You read up on kids having febrile convulsions, they might last up to five minutes and we had one 55-minute seizure, and one 25-minute one," Chad said.

"He went and saw one pediatric neurologist and he told us he believes she (Carli) had Dravet Syndrome."

CEO of the Epilepsy Foundation, Graham Shears, says the syndrome carries the risk of death.

"Getting the correct diagnosis through genetic testing is really important so they get the right treatment," he told ACA.

The family has been told by their neurologist that medicinal cannabis could help.

It's legal in Australia and has shown incredible results with other infants in similar in similar situations but bureaucratic red tape is holding up the approval process, frustrating the family.

"If we can get the medications that we require to be approved, we might stop that seizure, the one that's going to stop her from having the ability to speak or to walk," Mitch told ACA.

Mitch and Mark have often been referred to as the "villains" on the hit show and have been the target of many unflattering stories in tabloid magazines.

However, the couple say this real-life drama has put it all into perspective.

"I remember reading an article and then being in the hospital (visiting Carli) and I thought it doesn't matter, nothing can hurt us now," Mitch said.

"We can dust that (negative stories) off but we can't dust this one that we're dealing with now off."

Mark agrees.

"Our family is the most important and we will be there, always," he told ACA.