When Joshua P. Warren's miniature dachshund died, he started hearing whimpers that sounded like those Nellie used to make.
Initially, he brushed them off. But then, his fiancee heard them, too.
"I love to investigate haunted houses, but I don't like to live in one," Warren, a paranormal investigator and author, said with a laugh. "It's rare for me to break out the equipment in my own house."
But he did, and he discovered that Nellie's ghost was indeed in his North Carolina home.
"There were distinct and measurable energy patterns," he said, "but it didn't last long."
Nellie's death and a visit to the Jackson Farm in Lancaster, S.C. -- which he calls one of the most haunted places he's ever seen -- fostered the beginning of Warren's research into animal apparitions.
In his new book "Pet Ghosts: Animal Encounters From Beyond the Grave" (New Page Books, $14.99), Warren discusses the differences between human and animal ghosts, shares dozens of stories about pet ghosts and even explains how to conjure up your dead pet's spirit.
What may seem more bizarre is he is far from alone.
Pet ghosts are coming home, and they're doing so close to home here in the south suburbs and Chicago.
Will County Ghost Hunters Society founder and director Dan Jungles said he and the group's 1,300 members can do free investigations.
In one case they checked out, a couple who had just bought a home in Mokena reported seeing a cat that they could never find, Jungles said. It felt so real that the wife swore she felt it jump on the bed, he said.
When a neighbor told them about the previous owner's cat, which had been run over by a car shortly before they bought the house, they realized that cat fit the description of their apparition, he said.
"They still see it every once in a while, and it's been a year," Jungles said.
In Midlothian, a couple told Jungles they started to hear their 16-year-old dog's squeaky toys shortly after he was euthanized. And then they found those toys moved from a box near the back door and to a spot near the couch, which had been the dog's favorite place.
"They saw him one time together out of the corner of their eyes, and then he was gone," Jungles said. "They weren't scared. They were actually relieved and happy their animal was still around."
Ursula Bielski, a paranormal researcher for 20 years and owner of Chicago Ghost Hauntings Tours, recently read "Pet Ghosts." She agrees that people are very curious about their pets' afterlife.
"I think that trying to contact pets that have passed on is a positive thing, especially for children," Bielski said.
And it can be done, she said. Bielski has investigated several cases of cat "ghosts" over the years.
"We have gotten the same kind of evidence we get in human ghost cases -- Electronic Voice Phenomenon (EVP) of purring and video evidence such as 'orbs' in motion," she said.
"Usually, the family members will experience two things. They will see the cat out of the corner of their eye, usually jumping from one place to another. Or they will feel the cat walking next to them on the bed or couch, sometimes seeing the little paw indentations as well."
Pet ghosts tend to not stay around as long as human ghosts, Warren said, so it can be challenging to document their presence.
"The majority of the experiences occur right after death, within days or weeks at the most," Warren writes, "and the apparitions are usually described as 'shadowy forms.'"
The well-documented case at the Lancaster farm may convince even the toughest critics.
The farm stands on ground where American Indians had reportedly tortured white people, and later it was the site of a slave church for decades, Warren writes.
The Lancaster family reported several horses died unexpectedly in the same exact spot within a short time span.
Later, Lynn Jackson photographed the horses' apparitions at the farm and in her living room. She also took pictures of apparitions that resembled huge dragons or dinosaurs.
Like many other sciences, paranormal activity is based more on anecdotes than hard evidence.
"There is no proof pets can come back and interact with us," Warren said.
Therefore, anecdotes told by people who believe in pet ghosts are a major aspect of the work generated by Warren and his research team, L.E.M.U.R. (League of Energy Materialization and Unexplained Phenomena Research).
Warren, who also has written "How to Hunt Ghosts" and "Haunted Asheville," said many people have reported that they've seen their pets staring or crying at something invisible to the human eye. They may have been detecting a pet ghost, he said.
One more piece of lore: If you don't want your own pet to return after death but wouldn't mind spotting someone else's, head to the Los Angeles Pet Cemetery.
Movie stars and other prominent folks have buried their beloved canines and felines there. Over the decades, visitors have reported seeing pet ghosts playing in the graveyard.
The most well-known pet ghost there is Kabar, Rudolph Valentino's great Dane who died in 1929. He allegedly licks people who pass his grave, Warren said.
Vickie Snow may be reached at email@example.com or (708) 633-5981.