A NSW woman was in a rage over money when she assaulted her brother with a tyre lever before driving her car into a river as she fled police, a court has heard.

Louise Bittar had shown up at her brother’s Sydney house demanding money when she started hitting him with the implement in October of last year, Bankstown Local Court heard on Monday.

Richard Bittar said he punched his sister several times in self-defence before she tore off with police in pursuit.

“The rage she was in, I could have struck her a million times and it wouldn’t have made any difference,” he said.

Bittar would later that day have to be rescued from her sinking Toyota Yaris after driving it off a boat ramp into the Georges River.

The 33-year-old was found guilty of her brother’s assault on Monday and has previously pleaded guilty to negligent driving, destroying or damaging property and the police pursuit.

She has not yet entered a plea to charges of driving in a dangerous manner, driving at excessive speed and driving under the influence.

Her brother in a recorded police interview on the day of the assault said he’d been safekeeping some money she got in a payout and giving it to her as she required it.

He alleged she always blew the money on drugs, and had attacked him when he said he couldn’t give her some cash she’d requested until the following day. “She’s got hardly any bills, she’s got f*** all rent, today she wants $1000,” he said during the interview, in which he also alleged his sister was “heavily juiced on ice”.

Bittar, who has told the court she’s seeking drug rehabilitation, will remain in custody until her case is resolved despite making a bid for bail while her mother is in hospital.

Defence lawyer Uzma Abbas said her mother was critically ill in intensive care, and Bittar was also in danger of losing her housing.

But magistrate Kathy Crittenden ultimately found she posed an unacceptable risk to the community that couldn’t be mitigated by strict bail conditions. The magistrate considered the health of Bittar’s mother as well as Bittar’s criminal history and mental health issues in determining the “very difficult” release application.

The matter is next scheduled for court on January 31.