On Thursday, her uncle and aunt, Allan and Janice Robson, told Daily Mail Australia they suspected their beloved niece had met with foul play.
'It's just like she's gone off the face of the Earth. There's nothing,' Mrs Robson said.
'I would say that somebody would have been watching her. I can't think it would be anything else.'
'Any information (the police) have they'll sit on it. They don't want to spook anyone,' Mr Robson said.
Mr Robson said he asked his brother - Ms Murphy's father John Robson - if he knew of any reason why his daughter may have vanished, but he had no answers.
Mr Robson said his niece was financially secure and pondered whether someone may have hurt her in a robbery gone wrong.
'Mick had so many cars he couldn't fit them in his garage,' he said.
'I don't think it's an opportunist,' Mrs Robson said.
'I think it's been someone who has been stalking her. Someone who she didn't even know was stalking her.'
Mrs Robson suggested anyone who knew her niece knew she was a creature of habit when it came to exercise.
'She would routinely go for a run in the morning,' she said.
The heartbroken family of missing mum of three Samantha Murphy fear she was abducted by a deranged stalker who pounced while she was on a morning run.
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