Mr Lawrence first realised Brian was gone when he went to let him inside.
‘I’ve gone outside to let him back in because it’s hot … and he was gone,’ he told The Advertiser.
The 54-year-old claimed someone took advantage of Brian’s placid nature.
‘He’s such a friendly dog. If someone just said ‘Come on, let’s go for a drive’, he would just jump right in the car.’
Mr Lawrence offered a $2000 reward for the person who found Brian.
Watch the heartwarming video below from the MailOnline.