Alvin, a poodle mix, was in the back seat of the vehicle on June 4 when his owners say it was stolen in a split second.
Melissa Guachichulla said the 1-year-old dog was a member of the family and was in the car while her parents were inside a laundromat in Bloomfield.
The car was left running with Alvin inside.
"She looked outside and the guy was getting in the car and then he started driving away, my dad ran behind him and he didn't stop the car," Guachichulla said.
The car was later found near South 13th Street and Avon Avenue in Newark -- but Alvin was not there.
Video from a nearby homeowner said she saw Alvin with another person on her Ring camera. She had seen one of the posters that the family placed around the neighborhood where the car was abandoned.
Ashlee Graves works with More Than Bread Ministry along the street where the stolen car was found and said she remembers seeing Alvin.
"I saw the dog and I didn't know what to think, because it was a very odd character to be roaming on Avon Avenue but I didn't stop...I thought there's probably an owner nearby," Graves said.
The Guachichulla family has not stopped searching and is checking in regularly with the local animal shelter, hoping to be reunited with Alvin, who Melissa says needs special medication.
They say the Apple Airtag Alvin was wearing is no longer active.
Now they are hoping that someone with a heart will lead them to their beloved dog.
"My sister would sleep with him every night and it hasn't been the same anymore," Guachichulla said.
A reward is being offered for Alvin's safe return -- with no questions asked.
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