Jack Chivers, who was then 14, refused to go.
He had told his sister that her father, Frank, had been angry about her “pinching” money, and, in 2007, told police his father had said he was going to kill her.
Later, two of his friends saw her at a bus stop, he told Preston Crown Court, but he never saw her again.
Mr Chivers, now 22, said that a week after Paige’s disappearance in August 2007 he had discovered footprints on the window sill of their home in Longford Avenue, Bispham.
He told police it was “pretty much obvious” Paige had returned for more clothes.
Robert Ewing, 60, denies charges of murdering Paige back in 2007 and doing an act tended and intended to pervert the course of justice.
The prosecution claim that 15-year-old Paige was killed at Ewing’s flat on All Hallows’ Road, Bispham. Co-defendant Gareth Dewhurst, 46, of Duncan Avenue, denies a serious sexual offence, assisting an offender and also doing an act tended and intended to pervert the course of justice.
The prosecution have alleged that Ewing, who was known as Bob, had a sexual interest in the girl.
And it is also claimed that Dewhurst helped in disposing of Paige’s body.
Mr Chivers admitted he and Paige often fought, but told the jury: “I loved her. She still loved me. She’s my sister.”
He said the pair had been left to fend for themselves when their mother, Sheila, became ill, but family had come round to help.
Life became chaotic after their mother died in February 2007. His sister took money from their dad’s wallet and had also used his bank card shortly before she left, he told the court.
Eventually her father found out, was very angry and threatened Paige “and all sorts”, he said.
Mr Chivers admitted he told police in 2007 his father had threatened to kill Paige.
He said: “She said she was leaving, packed her bags and went. She walked down the street. I followed her down the street. She asked me to go with her at first.
“I said no, it would kill my dad, and mum had just passed away. She left, walking in the direction of Ashfield Road. Not long after that two friends of mine spotted her at a bus stop.
Later that day, dad returned from work and asked where she was. After being told she had left he just shrugged like it was nothing.
“He thought she would come back in a couple of days.”
At the time she went missing, Paige had been expelled from school. She was occasionally drunk and had been taking amphetamine and cannabis.
On one occasion, Mr Chivers told the court, her father had hit Paige five or six times on the head after finding out she had been taking his drugs.