Architect Joanna, 25, who lived with Greg in Bristol, was strangled.
Her body was found by walkers eight days after she went missing on December 17.
Greg, 27, reported her missing on Sunday, December 19, after he returned home from a weekend away in Sheffield. Police said on Tuesday they are not treating him as a suspect.
Greg's parents, Lydia and John Reardon who moved to Ilfracombe in 2004, have appealed for "every last scrap" of information to be given to police.
Lydia Reardon, 67, said: "Someone, somewhere may know the one crucial thing that helps the police solve this dreadful crime. Please just pick up the phone and tell them."
Earlier Mrs Reardon had spoken of when Greg called her when he arrived home.
She said: "He phoned me on Sunday and said 'I've just got home and Jo's not here'.
"At the time, I told him not to worry as she must have just nipped out. Then he said all her stuff was still there and later reported her missing."
The Ilfracombe family are believed to have joined the search for Jo before her body was discovered in the snow three miles from her home.
Mrs Reardon said it was love at first sight for her son, who is working towards his professional chartership.
The couple met at work at the Building Design Partnership in Bristol.
She described Jo as "very intelligent and popular".
Mrs Reardon told reporters: "She was a lovely, gorgeous girl. Greg brought her home and she stayed with us a few times. They had been together for a couple of years.
"Greg was so fond of her. We thought when he finished getting the last of his qualifications they would get engaged."
Greg told police he had tried to call and text Jo during the weekend he was away, but had not got a response.
He said he returned home to find Jo missing, but discovered her coat and bag containing keys and her purse inside their home, when he rang friends and family.
Greg appeared at a police press conference before her body was found, alongside Jo's parents, David and Teresa.
Greg told reporters: "I desperately want her back – I thought we would be together forever."
Her body was found by walkers eight days after she went missing on December 17.
Greg, 27, reported her missing on Sunday, December 19, after he returned home from a weekend away in Sheffield. Police said on Tuesday they are not treating him as a suspect.
Lydia Reardon, 67, said: "Someone, somewhere may know the one crucial thing that helps the police solve this dreadful crime. Please just pick up the phone and tell them."
Earlier Mrs Reardon had spoken of when Greg called her when he arrived home.
She said: "He phoned me on Sunday and said 'I've just got home and Jo's not here'.
"At the time, I told him not to worry as she must have just nipped out. Then he said all her stuff was still there and later reported her missing."
The Ilfracombe family are believed to have joined the search for Jo before her body was discovered in the snow three miles from her home.
Mrs Reardon said it was love at first sight for her son, who is working towards his professional chartership.
The couple met at work at the Building Design Partnership in Bristol.
She described Jo as "very intelligent and popular".
Mrs Reardon told reporters: "She was a lovely, gorgeous girl. Greg brought her home and she stayed with us a few times. They had been together for a couple of years.
"Greg was so fond of her. We thought when he finished getting the last of his qualifications they would get engaged."
Greg told police he had tried to call and text Jo during the weekend he was away, but had not got a response.
He said he returned home to find Jo missing, but discovered her coat and bag containing keys and her purse inside their home, when he rang friends and family.
Greg appeared at a police press conference before her body was found, alongside Jo's parents, David and Teresa.
Greg told reporters: "I desperately want her back – I thought we would be together forever."
http://www.thisisdevon.co.uk/news/Family-s-plea-Jo-murder/article-3047139-detail/article.html
