Reggie, a male merle French bulldog, escaped from the rear of owner Kat Quill's house in the Kingsway area of Heysham twelve days ago.
Mother-of-five Kat is appealing to anyone who knows his whereabouts to come forward with information in order to bring her beloved pet home.
She said: "It's absolutely devastating and we are worried sick. I have five daughters who have been left heartbroken.
Car on roof causes tailbacks in Morecambe
Man, 47, arrested after 70 car number plates in Lancaster and Morecambe are sprayed with paint
M6 reopens after vehicle transporting sheep overturns following crash between Preston and Lancaster
Morecambe 'neighbour from hell' back in court after breaching order
Morecambe takeaway scores two out of five for food hygiene
"On Sunday, September 12th, someone left our rear back gate open, so Reggie, along with two of my other dogs escaped. The two other dogs were found half an hour later near Hale Carr Lane, but Reggie was nowhere to be seen."
She added: "Reggie is chipped with a missing alert on his chip. He has a scar on his chin. He is only six months old and will be scared and confused. His last sighting on CCTV was on Hale Carr Lane on September 12th.
"We don't know where he is, which is quite worrying and we are now fearing someone has stolen Reggie. We've contacted local vets, the council and people have been kind enough to share the appeal on social media, but we've heard nothing."
Kat went ont o say: "I would appeal to anyone who has seen Reggie or knows information regarding his whereabouts to come forward. He's only six months old and will be scared and confused without us. Please do the right thing and hand him to a vet so they are able to scan and reunite him with his family."
Anyone who has seen Reggie or has information regarding his disappearance is asked to call Kat on 07470 270224 or 07799 558054.