Laura Bierer-Nielsen, 23, said her family hired a pet detective after their 15-year-old dog, Spillo, went missing on July 28, whilst they were on holiday in a cottage in Ingrams Green Lane.
The family have been using thermal camera equipment, three sets of professional sniffer dogs, and have put up more than 300 posters and leaflets.
Laura said: “There’s been no progress, we still haven’t found him.
"It’s been a horrible time but people have still been absolutely amazing in the area, out every day searching.”
Sussex Police said officers have been in contact with the owners to 'establish the full circumstances' and any lines of enquiry that suggested offences may have taken place have been 'proportionately pursued'.
The family believe Spillo was stolen but police confirmed they had found ‘no evidence’ to suggest this.
Chief Inspector Jon Carter, the district commander for the area, said “Speaking as someone who has dogs, I am very aware of the distress that this family are feeling, and I have written to the owners to explain the police enquiries that have been carried out."
If anyone saw a dog on or close to the road in the lane on that morning or has any other relevant information about this case, please contact the police online or by calling 101 quoting serial 666 of 31/07.
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