The 46-year-old woman became concerned when her dog was not returned home on Tuesday, and became even more hysterical when her dog walker sent her a text message that read: 'I'm really sorry, I think I left your dog in my car.'
The woman then rushed to the dog walking company's Rose Bay office in an attempt to rescue her beloved pet.
Passer-by Glenn Herne was on his way home with groceries when the woman abruptly approached him for help.
'She came over very upset and said she thought her dog was locked in a car,' he told. 'I couldn't see the dog because the car had tinted windows. The woman was hysterical and in tears. She was inconsolable.'
The car had a Signal Station Dog Walking sign pasted to its sides.
Glenn continued, 'I started tapping on the window to see if there was any movement but there was nothing.'
Glenn then went on to explain what happened when he smashed open the car's window to try and free the dog.
'I went to my ute and got a lump hammer to smash the back left window. There was a mesh screen in the way but I eventually got to the dog in the boot and tried to wake the dog up.
'He was rigid and still as a plank. His fur came out in my hand when I lifted him up. He was falling apart. The car was very small, warm and smelly so I put him on the grass.
'There was a towel in the car which I put over the dog and then neighbours came out and asked if it was a child.'
According to published reports today, it is believed the dog walker had left on a cruise.
Glenn further asserted, 'It’s ridiculous. I don’t know how you could forget. This woman is supposed to be a dog lover. You could tell by the way she parked her car that she was in a rush.'
The RSPCA has since been notified and the incident is being investigated by police.
The dog walker has not responded publicly to the incident, and has since removed the company's social media pages.
Anyone who finds a child or pet located in a vehicle are urged to call Triple Zero (000).