On Sept. 11, 2001, I was living here in New York and heard the sirens outside my window as fire trucks rushed to the burning towers. I felt dumbfounded and numb, and only my cat Toby, purring on my lap, brought me to a place where I could think again and try to help.

Toby wasn't the only pet who provided comfort that day. The Animal Planet series Saved aired a special episode about people whose pets helped them recover from 9/11.

When Maureen's firefighter sons Timmy and Tommy Haskell died in the Twin Towers, she says only the presence of Timmy's beloved Dalmatian, Blaze, "made my life worth living again." (See a clip from their segment above.)

And when 4-year-old Kate witnessed the attacks and became withdrawn and silent, only her family's new dog, Scout, helped her get over her trauma. (After the jump, a clip from Kate's segment.)

Dean is a big black dog, and they often get overlooked in shelters, but not Dean. That's because the staff at Sulfur Springs Animal Shelter in Texas was rooting for him. When Lexey Sparks of Mt. Vernon, TX, inquired about another dog she had seen on Petfinder and told shelter staffers her story, they recommended Dean.

"I have a now-7-year-old son with Down Syndrome," she says, "and I wanted to get a dog that could someday become his companion and therapy dog."

Lexey went to the shelter to meet Dean and "after only a few minutes, I just had this feeling that this was our dog, so I decided to adopt him then and there," she says. "That was one of the best decisions I ever made!"

Since the adoption, Dean has been neutered and treated for heartworm, "but he never lets anything get him down," Lexey says. "The vet was very impressed
with his attitude and said that he was one of the most well-behaved dogs he has seen in a long time. The vet thinks he is about 3 or 4 years old."

Wallace Mozart of Forked River, NJ, was browsing on Petfinder when he saw the listing for a three-legged German Shepherd named Buddy.

"I have always liked shepherds and have had shepherd mixes in the past," Wallace says, "so I decided to inquire."

The dog's foster mom responded promptly and told him that Buddy had been rescued from a yard where he'd been chained to a post.

The chain had become firmly wrapped around his leg, cutting off circulation and causing a wound that had become infected. A portion of his leg had to be removed.

Buddy was part of a group of dogs that were transported from Lenoir County SPCA in Kinston, NC, to Furry Angels Rescue in Elwood, NJ, to increase their chances of being adopted.

"I was interested in meeting Buddy and set up a meeting that next weekend," Wallace says. When they met, Wallace was impressed by what a friendly and happy dog Buddy was.

On Friday we shared an excerpt from Joanne Wannan's new book, New Lives: Stories of Rescued Dogs Helping, Healing and Giving Hope. (Read about Leo, a Pit Bull once owned by Michael Vick who became a therapy dog and Canine Good Citizen.)

Joanne's book is all about the ways rescued pets give us new lives -- and she's pledged to use her book to help shelter pets find new lives, too. Joanne's donating 50% of the book's profits for the months of October and November to a Petfinder.com member shelter or rescue group. This is where you come in.

Joanne Wannan is the author of New Lives: Stories of Rescued Dogs Helping, Healing and Giving Hope. Below is an excerpt from her chapter about Leo, a Pit Bull once owned by Michael Vick who became a therapy dog and Canine Good Citizen. Enjoy the story, and come back on Monday to find out about a chance to select your favorite shelter to receive 50% of the profits from the sale of New Lives for two months!

On April 25, 2007, Marthina McClay was relaxing in her living room watching television when a newsflash was broadcast. Property owned by NFL star Michael Vick had been raided, and approximately 50 Pit Bulls, allegedly part of a dog fighting operation, had been seized.

She sat bolt upright, stunned. "I don't believe it," she thought. And then: "I would really love to get one of those dogs and train it to do therapy work."

We're giving away four copies of the new book, Every Dog Has a Gift: True Stories of Dogs Who Bring Hope and Healing into Our Lives.

By Rachel McPherson, founder of the therapy-dog organization The Good Dog Foundation, Every Dog Has a Gift is about dogs who help people in incredible ways. Whether by lending an ear to a traumatized young girl, providing peaceful companionship during the final stages of life, or being an audience to a child as he practices reading, the dogs highlighted in this book are heroes to the lives they touch.

Want to win a copy? Leave a comment below and tell us what gift your pet has brought to YOUR life. Comments can be as long or as short as you like, just include the hashtag "#PFgiveaway," use a valid Facebook account or give us your email and post your comment before 11:59 pm April 17.

Four commenters will be randomly selected to receive a copy of Every Dog Has a Gift. (Terms & Conditions)

I look forward to hearing from you!

Guest blogger Rachel McPherson is the founder and executive director of The Good Dog Foundation in New York City and author of the new book Every Dog Has a Gift.

People frequently ask me how their dog can become a therapy dog. There is a common misconception that therapy dogs need to be a certain breed, or raised to be therapy dogs from a very young age. On the contrary, therapy dogs come in all breeds and sizes!

A therapy dog can provide healing to his or her companion or family, as well as hundreds of other people in a therapeutic setting - whether a hospital, a school or a retirement home. The remarkable work of therapy dogs (as well as service dogs and household pets) inspired me to write Every Dog Has a Gift. Likewise, I hope that readers will be inspired by the amazing stories in this book to do some good work with their own companion dog!

If you're interested in getting your dog certified, here are some tips to get you started:

• Find a reputable therapy-dog organization. If you're located on the East coast, visit TheGoodDogFoundation.org. If not, find an animal-assisted therapy organization in your state that offers a training program. There are a number of organizations mentioned in the book, and many can be found online as well.
  

As the marketing manager for Petfinder, I work out of the New York office of Animal Planet, where staffers volunteer every week to read with local elementary schoolers.

To celebrate the end of the school year, some of those students came to the offices on Friday, where they were treated to a presentation about pet care by Petfinder's public relations coordinator, Cary Moran.

Next, they got to met a real live Petfinder alum, Gwin. A 2-year-old corgi/sheltie mix, Gwin was adopted by Monica Hirsch and her daughter, Nora, from the Mercer County Humane Society in Princeton, WV -- and she's more than just a perfect pet, she's a certified therapy dog!