Patrick (left) and Barry Lyttle in happier times before assault in Sydney left Patrick in a critical condition in hospital

THESE are the once brothers-in-arms who have now left a family devastated and in despair over an assault in Australia.

Patrick Lyttle, 31, is fighting for his life in a hospital in Sydney after a family dispute spilled over on the pavement.

The family are Belfast, but Patrick had been living in Ballycastle, Co Antrim.

Brother Barry, 33, allegedly punched his younger brother in the head on Bayswater Road in Potts Point shortly before 3am on Saturday (4pm UK time) causing Patrick to fall backwards and hit his head on the ground.

It has led to a bleed and swelling on the brain.

Police say CCTV footage appears to show the siblings having a “minor” argument before Patrick pushes his older brother, who reacts by throwing a punch.

Alcohol has already been ruled out as an “aggravating factor” in the fight.

Patrick, who was treated by New South Wales ambulance paramedics before being taken to hospital, is on life support after undergoing emergency surgery to release pressure on his brain.

Paramedics attend to Patrick Lyttle in Sydney’s Kings Cross. 

His older brother, whose Facebook page is littered with photos of the pair posing with their arms around each other’s shoulders, was charged with recklessly causing grievous bodily harm.

Barry sobbed when he appeared at Parramatta Bail Court on Saturday afternoon.

He did not apply for bail and will appear back at the Central Local Court on Monday for a further hearing

The brothers had been out to dinner with their father in Sydney on Friday night before continuing on without him for a drink.

Patrick Lyttle had been keeping friends and family up-to-date on his Australian adventure via Facebook.

Patrick’s friends and family back in Northern Ireland had been keeping an eye on his travels around Australia.

After arriving in Sydney, Patrick travelled to Melbourne and started a road trip with mates along the Great Ocean Road on June 7.

By June 18, he was telling friends: “Another road trip to commence yeeooo!! To Adelaide, Alice Springs then Darwin.”

Barry appeared the doting older brother as Patrick posted photos of his adventures in Australia.

“Stay away from the edges ya mad man!!” Barry wrote after Patrick posted a photo of him standing on the edge of a cliff in Darwin. “Great pic though!!”

Patrick arrived back in Sydney late last year and was reunited with his brother and father, 74, three days ago.

The brothers, who have four older sisters, appear to be the best of friends in photos on social media.

Facebook shows the tight-knit family loved spending time together and the brothers revelled in spending nights on the town in each other’s company.

“Bros in arms,” their cousin Stephen wrote after Barry posted one snap of the pair together.

The Commander of Kings Cross police, Superintendent Michael Fitzgerald, said the men’s father was in shock.

“This is a tragedy,” he said. “We have a father who is facing the reality of one son facing serious criminal charges, another son fighting for his life.”