Sydney schoolgirl Michelle Levy, who had been missing since Saturday, had been "taken under someone's wing," her father said.

The 11-year-old was last seen on Saturday night when she left her North Bondi home after a family argument.

An extensive land-and-sea search was carried out on Sunday but the girl could not be located.

Her father, Adam Levy, said his daughter had been with an adult stranger since Saturday and is now safe and well.

"Our understanding is that someone took her under their wing on Saturday night when she was in Bondi Junction, and she's been with them until this morning," he said.

"She was spotted at Royal Randwick Shopping Centre ... apparently they went shopping.

"And by this morning, he's ... persuaded her to get in touch with us.

"She gave him our number and through an intermediary they've called us to let us know where she is".

Superintendent Jason Box from Waverley Police said a member of the public recognised the missing girl and contacted her mother.

He said the positive outcome was the result of "extensive media coverage and releases", and thanked community groups who helped in the search.

"It's extremely pleasing to see. When someone of a young age is missing, it's not only a concern of the police, but the community," he said.

"A fantastic effort all round by everybody."

Police have interviewed the man the girl stayed with and he has been released without charge.

Michelle Levy has returned home after staying with relatives this afternoon.

It was thrilling hearing her voice: mother

"We are very thrilled and we'd just like to say thank you to everyone who has been searching for her," mother Anne Levy said.

"It was just so thrilling [hearing her voice], I was in tears."

Police will continue to establish the grounds and reasons why the girl left her home.

Speaking before she was found, Mrs Levy said the family had expected her to go to the end of the street or her nearby grandparents' house to cool off after the argument.

"There was a small argument and she left and we didn't expect her to stay away for so long," she said.

"When we realised she was away for a lot longer period and we couldn't find her at her grandparents then we called the police straight away.

"It's been very, very hard these last few days."

Mrs Levy said she was thankful for the community support in helping to find her daughter.

"It just warms my heart to know the community cares so much," she said.

"I have been stunned by the response. It has been an amazing community response.

"Last night, the three separate search groups went out, one of which had over 1,000 people."