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NORTH PORT, Fla. (ABC4) – The sister of Brian Laundrie, a person of interest in the case of Gabby Petito, has shared images of postcards she received while the couple were on a cross-country road trip.

Throughout the summer months, Petito and her fiance, Laundrie, were on a cross-country road trip. After leaving New York, the couple entered Utah around August. Petito and Laundrie visited multiple areas in Utah and shared postcards with Cassie Laundrie – Brian’s sister – and her family.

“The rocks here are so cool!! Uncle Brian and I have seen many different rock-types, I knew there are different kinds of rocks, but I didn’t know that some are different formations, did you?” one postcard, appearing to be from Arches National Park reads. “The Rocks that are most popular in the park are called hoodoos, funny name right!”

The postcard, the second in the slideshow above, shows drawings of what appear to be the hoodoos and Delicate Arch at Arches National Park. Petito signs the postcard, like all the others, “Aunt Gabby.”

In another card, Petito appears to have drawn a brief map of northeastern Utah, adding “we are here” near “Canyonland,” presumably Canyonlands National Park. On a postcard believed to be from Garden of the Gods in Colorado Springs, Petito describes eating a snack with Laundrie and seeing “the fattest squirrel.”

During an interview with ABC News last week, Cassie Laundrie described Petito as being “like a sister,” adding that her “children love her.” Laundrie said at the time that all she wanted was for Petito “to come home safe and sound and this to be just a big misunderstanding.”

On Sunday, authorities searched Grand Teton National Park for Petito. In late August, Petito told her family they were visiting the park. Sunday evening, authorities recovered a body in the park that matches the description of Petito. While they are awaiting an autopsy – scheduled for Tuesday in Colorado – authorities announced the finding during a press conference, adding they have alerted Petito’s family of the discovery.

Following the news, Petito’s family took to social media to respond to the update.

Petito’s father, Joseph, posted his reaction on Twitter, saying “#GabbyPetito she touched the world.” As ABC4 affiliate WJW reports, Petito’s brother TJ posted a similar photo on Instagram, with the caption “I don’t even know what to say. I’m at a total loss. My heart is shattered.” Her uncle, Mike Schmidt, took to Facebook to thank everyone for the outpouring of support during the investigation.

The Laundrie family’s attorney released a statement as well, saying, “The news about Gabby Petito is heartbreaking. The Laundrie family prays for Gabby and her family.”

Authorities believe Laundrie went hiking in the 25,000-acre nature reserve last week. Dozens of law enforcement officers from numerous agencies searched Carlton Reserve over the weekend for Laundrie, calling it off around the time Petito’s body was found in Grand Teton National Park.