In the midst of tragedy, it's often the simplest acts that make the biggest difference.

Take what happened in Newtown, Conn., in December after a school shooting took the lives of 26 students and teachers, leaving the town experiencing a horror that few could have imagined.

As residents remained shocked, a group of golden retrievers showed up from Chicago to bring comfort to school children and townspeople alike.

PHOTOS: Comfort Dogs to the Rescue in Newtown

The dogs, part of the Lutheran Church Charities' K-9 Comfort Dogs Ministry, gave residents a glimmer of comfort and a second of joy they could not get elsewhere, just by wagging their tails and wanting to be petted.

Click HERE to learn more about the Lutheran Church Charities' K-9 Comfort Dogs Ministry.

"The dogs really helped us," one high school student from Newtown said.

Wearing their signature "Please Pet Me" blue signs, the 60-plus army of golden retrievers flock to communities like Newtown where lives have been upended by tragic events.

READ MORE: Dogs Comfort Bostonians After Marathon Bombings

The dogs have touched lives from Newtown to Joplin, Mo., site of a devastating tornado, to, most recently, Boston in the wake of the marathon bombings.

"I got to know the dogs a few days after the bombing," one bombing victim in Boston said. "They are incredible. They feel what you feel."

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"My house got destroyed by the tornado and once I saw them, they made me really happy," a tornado survivor in Joplin said. "Dogs are my best friends and they just really comforted me."

There's scientific evidence that dogs have a healing power around patients and people who've experienced traumatic events, said Dr. Emma Raizman, a pediatrician at the Cleveland Clinic Children's Hospital.

Being around dogs helps decrease patients' stress by prompting the release of oxytocin, which is the hormone that bonds mothers to babies. Studies have shown that patients who are around dogs have increased levels of dopamine - the "happy" neurotransmitter that helps relieve depression - as well as endorphins and adrenaline.

The man behind the K-9 Comfort Dogs Ministry, Tim Hetzner, says he has witnessed this firsthand.

"The comments we get all the time are thank you for bringing some joy," Hetzner, president of Lutheran Church Charities, said. "And then we will see kids come up and smile."

The K-9 Comfort Dogs and their hero owners got a chance to smile themselves today when they were honored on " Good Morning America" as part of "GMA's" "You're Not Dreaming!" series. The dogs, joined on "GMA" by Hetzner and their handler, Jen Marr, were surprised with a package of spa and grooming treats for the dogs and spa gift certificates from Bliss for their owners.

In addition, Hertz stepped up to help the ministry with one of its biggest expenses, transportation to get the dogs from crisis to crisis. Hertz announced on "GMA" they are providing K-9 Comfort Dogs Ministry with a free van for one year.