Signs to welcome Sandy Hook Elementary students are placed near the former Chalk School in Monroe, Conn., on Jan. 3, 2013. It was students’ first day of classes after the shooting in Newtown, Conn., in December 2012. (Jessica Hill/AP)

A turtle was an integral part of the routine at Sandy Hook Elementary School.

It was a standard-issue turtle named Shelley. A red-eared slider with a mottled shell the color of a catcher’s mitt. Yellow belly. Scaled flippers. Red marks on his head like racing stripes. Shelley was donated to Sandy Hook about a decade before the massacre there, according to the Newtown Bee. Children took turns feeding Shelley, sometimes spelled Shelly.

And when 500 elementary students from Newtown, Conn., returned to their desks in 2013 less than a month after 20 classmates and six adults were gunned down, Shelley was there bobbing in an aquarium, a welcome reminder of the time before gunman Adam Lanza stalked through the hallways.

“All the kids love Shelley,” Karen Dryer, the mother of a then-5-year-old Sandy Hook student, told ABC News at the time. “Just seeing Shelley was a huge thing for the kids, knowing he’s okay and that he’s going to be at the new school.”

This week, another shattered student body returned to the classroom. On Wednesday, Marjory Stoneman Douglas High School in Parkland, Fla., reopened after a Feb. 14 massacre that left 14 students and three adults dead.

The first day back at school after a shooting, boxed in on all sides by roaring politics and news coverage, plays out differently each time. When Columbine High School in Littleton, Colo., let students back four months after a massacre there in 1999, parents formed a human chain around the school to keep reporters at a distance.

When classes resumed at Chardon High School outside Cleveland after three students were killed in February 2012, classmates met in the town square, then marched into the school with linked arms while singing the alma mater.

When Sandy Hook’s children came back, they had Shelley.

A school bus traveling from Newtown, Conn., to Monroe on Jan. 3, 2013, stops near 26 angel signs posted along the road on the first day of classes for Sandy Hook Elementary School students since the massacre there on Dec. 14, 2012. (Jessica Hill/AP)

As Sandy Hook returned to school on Jan. 3, 2013, the plan was to, as one district official told CNN, make the event as “normal routine as possible.” The school was an active crime scene, so a small army of volunteers worked overtime to set up a carbon copy of Sandy Hook in an empty school building in a nearby town. Each desk and classroom poster and crayon traveled the eight miles to the new building and were arranged in the same order.

A Shelley-like red-eared slider turtle. (iStock)

Shelley came, too, the unsung hero of Sandy Hook’s healing process. The twenty-something reptile became a concrete symbol of continuity for children facing a seismic trauma.

“It may not seem like a big deal,” Dryer said on a parenting blog in 2013. “But for those kids to be able to walk into their new library and see their old librarian and Shelly, was just such a blessing.”

Piecing together as much of the normality wrecked by violence is recognized as a key to processing such events, particularly for children.

“When you return to familiarity in a situation that feels really comfortable, that will really help restore your previous beliefs, and restore that worldview that might have gotten shaken up by the trauma,” Jamie Howard, a clinical psychologist specializing in post-traumatic stress, told ABC News after the shooting. “It’s really important to maintain routines as quickly as possible.”

Almost a year before the incident, in January 2012, the student body began a fundraising campaign to upgrade Shelley’s accommodations.

“Shelly has outgrown her tank!” the Sandy Hook newsletter said. “For every dollar donated to the Shelly Fund, each donor will have a turtle with his/her name on it placed in a ‘tank’ on the wall in the cafeteria and receive one raffle ticket for a chance to win one of multiple fun prizes.”

Following the bloodshed at Sandy Hook, as information about the school filled international news reports, the public stature of the school’s turtle also grew. Elementary classes and college students from around the country, hearing about the school’s reptilian mascot, mailed stuffed turtles to Sandy Hook advisers. One art class at Ruth K. Broad Bay Harbor K-8 Center in South Florida donated a three-foot fiberglass turtle named Ruth to Sandy Hook to join Shelley.

“It’s our gift,” teacher Maggie Vidal-Santos said at the time.

The turtle remained with the Sandy Hook student body as it stayed in the temporary location for 3½ years. During that time, school and civic leaders weighed the key question of what to do with the site of the massacre. Eventually, the old Sandy Hook school was torn down and replaced with a $50 million building on the original site.

In a sign of the turtle’s continuing importance to the school, the new structure was outfitted with an aquarium for Shelley near the entrance.

“When students come in that front door, they’re going to see their turtle,” Patricia Llodra, a Newtown first selectman, told CNN at the opening in July 2016.

Llodra expanded on the thought to “Our focus has always been to bring our students and our teachers back to our community. It was important to the kids who’ll be coming to school here every day to know that Shelley was coming home too.”

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