The Jodi Jones murder trial has heard that her boyfriend Luke Mitchell had remained calm when her body was found near Easthouses.
Jodi Jones was 14 when she was killed in June 2003
The High Court in Edinburgh has been hearing Jodi's sister Janine describe the night her body was discovered.
The proceedings were taking place in a specially built court room where a replica was built of a wall close to where the teenager's body was found.
Mr Mitchell, 16, denies murdering 14-year-old Jodi.
Ms Jones, 19, said that late on the night of 30 June, 2003, she, her grandmother Alice Walker and her fiancÚ Steven Kelly had gone looking for Jodi.
She told the court they had received distraught phone calls from her mother saying Jodi had not returned home.
The group had gone to the Roan's Dyke country path, on the outskirts of Dalkeith, Midlothian, where they met Mr Mitchell, who had his dog with him.
They all walked back down the path and when Mr Mitchell was asked if he had seen anything, he said he had not and he seemed "his usual self".
When they arrived at a V-shaped opening in the wall Mr Mitchell went over.
Ms Jones said: "We heard Luke shouting there was something there or he had found something."
She said she and Mr Kelly ran back and saw Mr Mitchell standing on the other side.
"I think he said something along the lines of he didn't know what was there," said Ms Jones.
Prosecuting advocate depute Alan Turnbull QC asked how he looked and Ms Jones said: "He was fine."
"Did he seem different from normal in any way?" Mr Turnbull asked and Ms Jones replied "no".
Mr Kelly went over the wall and Ms Jones said that when he returned: "He seemed shocked. He said he didn't know what it was."
She told the court: "I was very agitated and anxious to know what was there."
Asked about her grandmother she said: "She was getting very agitated. She wanted to go over and check for herself."
Mrs Walker was helped over the wall to where Mr Mitchell was standing and Mr Kelly was "very agitated and shocked."
Ms Jones said: "He was just mumbling. Said he didn't know what it was or whether it was Jodi or what."
Janine Jones and her mother leave court
Ms Jones said that after her grandmother disappeared from view she heard her scream.
"I myself then started screaming," she told the court, saying she became upset because she thought Jodi was there.
Ms Jones said that by now her grandmother was "a mess."
She told the court: "She was really agitated, shaking, saying she didn't know if it was Jodi."
She told the court Mr Mitchell was still on the other side of the wall.
"He was fine," she said.
Earlier the court heard evidence from a scenery maker at Edinburgh's Lyceum Theatre.
He had made a 40ft replica of the section of the Roan's Dyke wall including the V-shaped hole.
Mr Mitchell has lodged two special defences, one of alibi and one of incrimination
The trial continues.