But now some of them are being reunited thanks to the Humane Society's Sandy NJ Pet Rescue.
Kayla Patterson and her 5-year-old daughter Jazmyn were among the evacuees who left behind their 7-month-old kitten Fluffy.
"I left a big bowl of water, dry food and wet food thinking it would be 2 to 3 days at the most, and then once it turned out being what it was, I was absolutely devastated. The guilt I felt, you have no idea," said Kayla.
Friends of Kayla's contacted the Humane Society, which went in to flood-ravaged communities at the Jersey Shore and rescued over 200 animals in Monmouth and Ocean Counties alone.
Kayla feared that Fluffy might have been killed in the flooding and fires. But like some other lucky animals, the orange fur ball was found, taken to a temporary shelter and this week was reunited with her now displaced family.
"I was telling everybody I think we need to switch her name to my little survivor because it's just such a blessing for her to survive that," said Kayla.
Jazmyn feels blessed to have Fluffy back, and she is already looking ahead.
"For Christmas, I want a house for me and my mom and my kitty," said Jazmyn.
If you are trying to locate a pet left behind or rescued in the storm, call the Humane Society's Hurricane Sandy NJ Pet Rescue Hotline at 609-384-0306.
Fluffy seems unfazed by all that has happened, and Kayla says they can't thank her rescuers enough.
"I still can't believe she's here. It's absolutely amazing," she said.
It is unclear if and when Kayla and her daughter will be able to return to their home, but at a time when their world has been turned upside down, there is comfort knowing they didn't lose their beloved Fluffy.