In February, an active shooter opened fire at a high school in Parkland, Florida, killing 17 students and leaving the nation grieving once again. While the tragedy sparked outcry—especially here in Colorado, ground zero for two of the county’s most shocking mass shootings—the distance made it difficult to offer support to survivors. But at least one Coloradan made a direct impact in the healing process. That Coloradan was a Golden Retriever named Cubby, who traveled all the way from Fort Collins to provide her service.

“The kids in Florida had just returned to school after the shooting, and by the third day we were there, they would come running over to us,” says Bonnie Fear, one of Cubby’s handlers. “It’s good to see that excitement, and that level of happiness after that horrible situation.”

Cubby is one of 130 golden retrievers across the United States that is ready to be deployed to tend to trauma survivors anywhere in the country. Trained by Lutheran Church Charities (LCC), which is based in Illinois with a satellite program in Colorado, Cubby has offered her services to Parkland students, as well as survivors of October’s mass shooting in Las Vegas. When she isn’t supporting victims of tragedy, Cubby makes regular visits to hospitals and schools in Fort Collins. And while she is the only LCC dog currently active in Colorado, Cubby isn’t the sole support dog in the Centennial State.

Cubby comforts a survivor of the Las Vegas shooting in October

Animals 4 Therapy, a therapy animal training organization based in Golden, provides similar services. In 2015, the dogs were on assignment during the Aurora theater shooting trial, where they waited in a media-free victims area outside the courtroom. Survivors of the shooting, as well as people affected by the violent images displayed during the trial, were able to spend time with the animals as a way of dealing with the trauma.

“[These] dogs have to essentially be bomb-proof,” says Kateri Nelson, executive director of Animals 4 Therapy. “When you train a therapy dog, you train them to be OK with everything. They have to be OK with noises and people crowding them. You must be sure they are not going to get scared of things around them, whether it is people or different types of equipment.”

The concept of comfort animals has become muddled recently, with tales of people unscrupulously labeling their untrained pets “emotional support animals” in order to gain access to places where animals are not normally allowed. Yet properly trained comfort animals are necessary. While they differ from service animals in that they don’t perform specific tasks and are not protected by the Americans with Disabilities Act, they do handle people experiencing extreme emotional states.

“Dogs lower our blood pressure, and are basically comfort rugs with a heartbeat,” says Tim Hetzner, director of the LCC Comfort Dog program. According to a 2013 Harvard Medical School study, having a dog or cat significantly reduced the blood pressure of people in high-stress situations. Both adults and children as young as three showed lowered cardiovascular reactions after actively petting dogs. Scientists believe that petting or playing with a dog decreases the stress hormone cortisol.

Training for comfort dogs starts early. At eight weeks old, for instance, LCC dogs are fitted with tiny vests to help them acclimate to wearing them daily. They are eventually trained to handle unknown people petting them, as well as to work in various environments with different surfaces. At 10 months, Cubby was sent to the Fort Collins LCC program and became one of the youngest dogs to begin regular assignments around her community.

Unlike the LCC program, Animals 4 Therapy is not breed-specific and will train shelter and rescue dogs. For example, one of the dogs had been abandoned on the side of a road in Texas with two BBs in his leg. “He was hurt and emaciated,” Nelson says. The rescue organization that saved him got to know his personality and recommended him as a therapy dog. “He’s been successful and really a gem. Our dogs have great stories.”

Dogs from Animals 4 Therapy work in a variety of settings. “We have some dogs that love working with veterans and are super active—the vets love that,” Nelson says. “Other dogs really enjoy working with patients. Some people have nerve damage and require something called ‘lick therapy.’ Someone puts peanut butter on the person’s arm and the dog licks it off, and the patient responds with a description of the sensation.”

Trauma, whether personal or national, can create prolonged stressful reactions—not just for survivors, but also community members or even the media. Comfort dogs provide a respite from both painful memories and the new realities that many people face.

“The Parkland kids reacted the same as the Las Vegas community when the dogs showed up—big smiles and a “This is the best part of my day!’ Fear says. “At least temporarily, they can forget about the crisis that they are dealing with.”