Wednesday
The family of missing teenager Cassie Olczac say her disappearance is completely out of character.
Mother Connie Olczac said Cassie had returned to Sydney from Abu Dhabi on Saturday after visiting her father.
"She came off a plane 7pm Saturday night, she came home, she ate, went to bed, was eager to meet up with her friends the next day," she said.
"The next day her sister drove her to her best friend's house, they said she was fine ... as the day went on she was highly agitated and they told her to go home and get some sleep.
"They last saw her at 6.58pm at Banksia station heading south. No CCTV confirms her getting off a train."
Mrs Olczak said there had been reports of someone fitting Cassie's description and wearing the same clothing sleeping on the 5.37am train from Blacktown to Emu Plains with a pink blanket.
She said she did not know why her daughter would be in that area. Cassie has not accessed her bank account and her phone has been switched off since 8pm on Sunday.
Mrs Olczak said she had contacted her daughter's friends and no one had any idea where she was.
"She's a quiet kid, she won't go where there's a lot of people," she said. "She's not street smart."
Tuesday
Police are urging the public’s help in finding a missing Sylvania teen.
Cassie Olczac, 16, was last seen about 6.30pm on Sunday after getting off a southbound train at Banksia to catch a connecting train.
Police have been told Cassie was supposed to continue on to Hurstville, but it’s not known if she arrived there.
She was reported missing later that night by family.
Police have conducted extensive inquiries to try and locate her but so far have been unsuccessful.
She is described as being of Caucasian appearance, about 175cm tall with a thin build and dark brown hair.
She was last seen wearing a multi-coloured shirt, grey tights and white and gold Adidas sneakers.
Anyone with information should call Crime Stoppers on 1800 333 000.