WATCH: Would you walk past a lost child?

IT'S A Saturday in Australia's busiest pedestrian mall.

Two children, Samuel and Ava, take turns standing in the middle of the mall, appearing to be alone and frightened.

Will they be approached and offered assistance or will shoppers simply walk by?

At first, many people walk by, distracted or unwilling to help, but it's only minutes before the first person approaches.

"Hey sweetie, when's the last time you saw your mummy and daddy?"

The concerned young lady proceeds to ask Ava if she wants to come to the information desk or wait to see if her parents appear.

Two women then spot Samuel, "Hey buddy, where's your mum?" Are you alright, mate?" they ask.

Key Assets' Executive Director, Rob Ryan said he was surprised by the number of people who walked past.

"When you are in Australia's busiest pedestrian mall with thousands of visitors, it is sad to see that in eight hours, only 21 people offered to help the children.  It really is the perfect metaphor for what is happening to children in need. 

"There are more than 43,000 children in Australia that need care and protection. This number has been steadily increasing over the past 10 years, but the number of foster carers is in decline.

"We hope that this social experiment will help bring attention to the desperate need for more foster carers in Australia and encourage those who have never thought about it, to reach out to us," Mr. Ryan said.