The father works in construction and was at work at the time of the alleged kidnapping.
The alleged offender, Mr Ji, faced court last week after he was arrested at his Mitcham home by heavily armed police from the Special Operations Group on the night of August 23.
The 36-year-old was charged with two counts of kidnapping, aggravated burglary, armed robbery, false imprisonment, three counts of common law assault and theft of a motor vehicle
The Melbourne Magistrates Court heard Mr Ji knew the victims and that he had allegedly detained the two children with the intent to demand a $1 million ransom.
The court documents also show Mr Ji was allegedly in possession of a knife at the time and also took a Telstra SIM card from inside the property.
Three other people were arrested at the Mitcham property and questioned but later released without charge.
Neighbours said the arrests were dramatic, with one woman telling The Age she heard a car roaring down the driveway next door.
“I could see the lights, and straight away they were telling them to get out, to get on the ground. One of them arrested was howling and crying. Just kept whimpering and crying.”
She said she then saw the children being carried to a car by police officers.
“I saw the kids carried away, you could see the police carrying them and saying, ‘You’ll be fine, you’ll be safe now’,” she said.
After the children were reunited with their parents, police said they were in good spirits and displayed “resilience beyond their years”.
“They were really quite remarkably docile and at peace with things,” Commander Mick Frewen said last week.
Anyone with more information is urged to contact Crime Stoppers on 1800 333 000 or visit crimestoppersvic.com.au.
With Erin Pearson
The Morning Edition newsletter is our guide to the day’s most important and interesting stories, analysis and insights. Sign up here.