Catherine Brown told a contested committal hearing at the Ballarat Magistrates’ Court on Wednesday her partner, Thomas Callum Huby, was getting up multiple times during the night to attend to their daughter.

She said the family had not slept well the night before the fatal crash in Cardigan on April 23, 2016, and Huby had not slept well for a week.

But she said she let Huby take their daughter, Isabella Huby, from Beaufort to Ballarat the following day.

“He is a fantastic driver and I will stand by my word on that. He looked quite good, surprisingly, otherwise I would not have let (Isabella) go,” Ms Brown said.

Respiratory and sleep disorder expert Professor Matthew Norton testified Huby’s alleged driving behaviour before the crash suggested he was experiencing a series of micro sleeps.

He said a witness’ statement describing Huby travelling along Remembrance Drive 50 metres behind another vehicle, that was behind a truck, swerving and appearing to try to overtake showed he may have been micro sleeping.

“To me that is a classic fall asleep motor vehicle collision,” Professor Norton said.

One of the first witnesses on the crash scene, Matthew Kennedy, told the court he overtook Huby before taking the off-ramp to Remembrance Drive at 2.35pm.

Mr Kennedy, a Horsham police custody officer, said his speed slowed to 90kmh because he was behind a truck carrying a tractor.

He said he checked his right-hand mirror three times and saw Hubby’s red car 50 metres behind him marginally on the line.

“Like he was poking his nose out to have a look. My thoughts were he was no way able to pass me and the truck,” Mr Kennedy said.

As he went to overtake the truck, he checked his mirror and saw Huby’s car “bounce off a tree”, Mr Kennedy said. He said he saw Huby get out of the car quickly before getting the child out.

“He was saying he loved her, he was sorry. Please wake up,” Mr Kennedy said.

Four-year-old Isabella Huby was taken to Ballarat Health Services Base Hospital but died on arrival.

Huby, 25, faces six charges, including culpable driving, dangerous driving causing death and driving while drug impaired.

The hearing continues on Thursday.