The phone call that shattered the brother of a travel-loving Sydney teacher

A heartbroken brother was shattered by an unexpected phone call from police in Sydney that his travel-loving sister was allegedly killed by her partner thousands of kilometres away.

Catiuscia Machado left Brazil for Australia in March to come and teach and improve her English.

She and her brother Paulo were always close, despite the distance.

But Paulo was devastated when he received a call from NSW Police officers while at home in Brazil informing him his sister had allegedly been murdered.

"I'm broken inside, being far way you feel so … I'd really like it if she was near me to watch more closely what was happening – maybe if she was here, none of this would have happened," he told 9News.

"It was the worst night ever of my life.

"You wake up like that and your sister is dead."

Police allege Machado and her boyfriend Diogo De Oliveira had fought on Friday night while she was running a bath at their Chiswick unit.

De Oliveira allegedly pushed her and she hit her head and fell into the bathtub.

9News understands police were called by a friend of De Oliveira on Saturday night after receiving a phone call from the accused.

It is also understood that police arrived to find Machado's body in the bathtub along with packets of frozen food.

Machado's brother claimed he spoke to her earlier on Friday, where she told him she wanted to end the relationship and return to Brazil.

"She was a reserved person, she didn't like to talk about her relationship," he said.

Friends said the couple were due to fly to South-East Asia for a holiday and had been allegedly clashing over money.

De Oliveira faced court yesterday after being charged with domestic violence-related murder where he was refused bail to appear again in late January.

Machado's family has been plagued by tragedy after her other brother was accidentally shot dead in a game of cops and robbers when he was 11 years old.