Story highlights Children need to be with their families as quickly as possible after exposure to tragedy

Getting back to routines and having proper support enables children to do well

Kids who were already having issues at home may be more severely affected

School shootings such as the one at Sandy Hook Elementary in Newtown , Connecticut, may have long-lasting consequences, but with proper support, many children are able to move on, experts say.

Children need to be with their families as quickly as possible after exposure to such horrific events, said Steven Marans, director of the National Center for Children Exposed to Violence/Childhood Violent Trauma Center at Yale University's Child Study Center.

Marans and colleagues are making themselves available to Connecticut officials, including the governor's office and state police.

The good news is that most kids do bounce back from a single incident of trauma, said James Garbarino, professor of psychology at Loyola University Chicago and author of "Lost Boys: Why Our Sons Turn Violent and How We Can Save Them." If children can get back into their normal routines and get proper support, he said, they will do well.

Declan Procaccini, father of a third-grade student at Sandy Hook, told CNN's Wolf Blitzer his daughter was in a reading class on Friday when she and a teacher "heard bangs." The teacher locked his daughter and another teacher in a bathroom until police escorted them out through a messy scene.

Photos: Photos: Newtown school shooting Photos: Photos: Newtown school shooting Newtown school shooting – Children in Newtown, Connecticut, return to school on December 18, 2012, four days after the shooting at Sandy Hook Elementary School. Hide Caption 1 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Connecticut State Police officers search outside St. Rose of Lima Roman Catholic Church in Newtown, Connecticut, on Tuesday, December 16, after a threat prompted authorities to evacuate the building. Investigators found nothing to substantiate the reported threat, a police official said, declining to provide additional details. The church held Sunday services following the mass shooting at Sandy Hook Elementary School in Newtown. Hide Caption 2 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Connecticut State Police officers walk out of St. Rose of Lima Roman Catholic Church after the Newtown church received a threat December 16. Hide Caption 3 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Firefighters attach black bunting to a fire truck as a memorial at the fire station down the street from the Sandy Hook Elementary School in Newtown, Connecticut, on Saturday, December 15. Hide Caption 4 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Connecticut Chief Medical Examiner H. Wayne Carver II talks to the media about the elementary school shooting during a press conference at Treadwell Memorial Park on December 15. Hide Caption 5 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Zulma Sein is hugged by a family member outside of the entrance to the Sandy Hook School on Saturday. Hide Caption 6 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Police officers keep guard at the entrance to the street leading to the Sandy Hook Elementary School on Saturday, December 15. Hide Caption 7 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Connecticut State Police Lt. Paul Vance addresses the press on December 15. Hide Caption 8 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Police officers stand at the entrance to the street leading to the Sandy Hook Elementary School on December 15. Hide Caption 9 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Corinne McLaughlin, a student at the University of Hartford, bows her head during a candlelight vigil at Hartford, Connecticut's Bushnell Park on Friday, December 14, honoring the students and teachers who died at Sandy Hook Elementary School in nearby Newtown earlier in the day. Hide Caption 10 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Distraught people leave the fire station after hearing news of their loved ones from officials on Friday. Hide Caption 11 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Emergency workers stand in front of the Sandy Hook Elementary School in Newtown. Hide Caption 12 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – A child and her mother leave a staging area outside Sandy Hook Elementary School in Newtown, Connecticut, on December 14. Hide Caption 13 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Members of the media converge on December 14 in front of an apartment at 1313 Grand Street in Hoboken, New Jersey. The apartment is believed to be connected to the Connecticut elementary school shooting. Hide Caption 14 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Faisal Ali, right, of Colorado Springs, Colorado, joins other people outside the White House on December 14 to participate in a candlelight vigil to remember the victims of the Sandy Hook Elementary School shooting. Hide Caption 15 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Connecticut State Police spokesman Lt. J. Paul Vance, center, briefs the media on the elementary school shootings during a press conference at Treadwell Memorial Park on December 14 in Newtown. Hide Caption 16 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – People weep and embrace near Sandy Hook Elementary School on Friday, December 14. Hide Caption 17 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – A woman leans on a man as she weeps near Sandy Hook Elementary School on December 14. Hide Caption 18 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – President Barack Obama wipes a tear as he speaks about the shooting at Sandy Hook Elementary School during a press briefing at the White House on December 14. Hide Caption 19 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – A woman weeps near the site of a shooting at Sandy Hook Elementary School on December 14. Hide Caption 20 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – A woman weeps near Sandy Hook Elementary School on December 14. Hide Caption 21 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – People comfort each other near Sandy Hook Elementary School on December 14. Hide Caption 22 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – A man takes in the scene near Sandy Hook Elementary School on December 14. Hide Caption 23 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – A young girl is given a blanket after being evacuated from Sandy Hook Elementary School on December 14. Hide Caption 24 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – State police personnel lead children from the school. Hide Caption 25 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Children wait outside Sandy Hook Elementary School in Newtown, Connecticut, after the shooting. Hide Caption 26 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – A boy weeps at Reed Intermediate School after getting news of the shooting at Sandy Hook Elementary School on December 14. Hide Caption 27 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – FBI SWAT team members walk along Dickinson Drive near Sandy Hook Elementary School on December 14. Hide Caption 28 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – An aerial view of Sandy Hook Elementary School in Newtown, Connecticut on December 14. Hide Caption 29 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Connecticut State Troopers arrive on the scene outside Sandy Hook Elementary School on December 14. Hide Caption 30 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – A Connecticut State Police officer runs with a shotgun at the Sandy Hook Elementary School in Newtown on December 14. Hide Caption 31 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Police patrol the streets around Sandy Hook Elementary School on December 14. Hide Caption 32 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – People try to deal with the shock of the attack outside Sandy Hook Elementary School on December 14. Hide Caption 33 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – Connecticut State Police secure the scene of the shooting on December 14. Hide Caption 34 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – People embrace outside Sandy Hook Elementary School on December 14. Hide Caption 35 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – A man escorts his son away from Sandy Hook Elementary School on December 14. Hide Caption 36 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – People take in the news outside Sandy Hook Elementary School on December 14. Hide Caption 37 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – People line up to enter Newtown Methodist Church near the the scene of the shooting on December 14. Hide Caption 38 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – A woman speaks with a Connecticut state trooper outside Sandy Hook Elementary School on December 14. Hide Caption 39 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – The streets around Sandy Hook Elementary are packed with first responders and other vehicles. Hide Caption 40 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – A view of the scene at Sandy Hook Elementary School after the shooting. Hide Caption 41 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – A young boy is comforted outside Sandy Hook Elementary School on December 14. Hide Caption 42 of 43 Photos: Photos: Newtown school shooting Newtown school shooting – People embrace each other on December 14. Hide Caption 43 of 43

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"I don't know if my daughter's in shock or not, but from what she told me she saw, she's doing incredibly well," Procaccini said.

Procaccini's 10-year-old son is also doing well, he said, but there are still fears of a repeat incident.

"My kids are already asking, 'When is this going to happen again?' It was only a week ago that we were talking about this type of situation, and I said the chances of it happening are one in a zillion at Sandy Hook. I was wrong about that."

Long-term issues are more likely for children who were very close to someone who died in a shooting, who witnessed the event or who were in close physical proximity to it, Garbarino said.

In addition, "Kids who are having difficult lives before the event are the ones most likely to have issues," Garbarino said.

For instance, if a child's parents are going through a divorce or if the child had been fighting with a parent on the day of the event, he or she may feel more of an impact from a traumatic event such as a school shooting, he said.

Moreover, if a child is frequently exposed to violence, such as by living in an abusive household or a dangerous neighborhood, a school shooting may add to existing trauma that child has stored up, Garbarino said. In those situations, it's hard to lean on the idea of "going back to normal."

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There is evidence that elementary-school children are particularly vulnerable to trauma, more so than teenagers or adults, Garbarino said. This may be because although these children have enough awareness of a situation to appreciate danger, their brains and bodies haven't matured to manage the effects in the way teenagers and adults can.

Symptoms

Trauma from a school shooting can manifest itself in physical ways, such as stomachaches, headaches and sleeping difficulties, said Nancy Rodda, senior director of clinical services for Genesee County Community Mental Health in Flint, Michigan. In Rodda's county, a 6-year-old boy shot a 6-year-old girl to death at an elementary school in 2000.

Stress can instigate a variety of behaviors: For instance, anxiety can lead to poor eating, which can lead to stomach discomfort, Rodda said.

Alexis Wassick, a student at Sandy Hook Elementary, said Friday that "people were even like, they kind of got a stomachache."

Kids may start depending on their parents for things they're normally able to do on their own, Marans said. They may also become more irritable.

It's not only a single event that puts children at risk for developing long-term mental health problems such as post-traumatic stress disorder, anxiety and depressive disorders, Marans said. How well they were doing before a school shooting will have a big impact.

There also is the issue of survivor's guilt , Rodda said. Children who have lost friends may wonder why they themselves lived.

Support

One of the best predictors for good outcomes is when kids have adequate support from their families and communities, Marans said.

Parents should listen to their children, reassure them that they are safe and look out for any changes in behavior, Rodda said. Let children ask questions, and don't force anything on them, Garbarino said.

"There's a balance between talking about it but also not dwelling on it too much," Rodda said. "Overexposure can increase stress."

Procaccini said he's been talking to his children, explaining what happened. "You do your best to communicate with them," he said.

Getting back to routines is key for children to move on, Garbarino said. If Friday is usually pizza night, have pizza. If swim practice usually happens on Saturday, take your child to swim practice at the normal time.

If children are too scared to return to school, parents should try to go with them as far as they will go, Garbarino said. If a child becomes hysterical upon arrival, take him or her back to the car and see if you can ease the fear, he said. Avoid reinforcing the fear.

"Hopefully by the time they do go back to school, I'll have done a good enough job at talking to my kids and make them feel at least the most comfortable they could," Procaccini said.

It's important for adults to get the help they need, too, Marans said, so they can be resources for the children who need them.

"It's such a convergence between our worst nightmares coming true, and there is a sense of helplessness and loss of control that we need to address," he said.

Interventions include helping parents understand the emotional consequences of an event like this and what to look for in their children.

The Child & Family Traumatic Stress Intervention program, which was developed at Yale at Marans' center, aims to increase communication between parents and children and prevent longer-term disorders.

When other risk factors are present that make recovery more difficult, there are other strategies. These include trauma-focused cognitive behavioral therapy, a specific type of psychological therapy that targets thinking and behaviors.

"With the right help, children are very resilient," Rodda said. "We have many different ways to help people who have experienced a trauma now that allow them to come out on the other side as survivors."

Based on experience, Garbarino estimates that 85% of kids would return to normal functioning, from a mental health standpoint, within a year after an event like the Connecticut shooting.

"Not to say they would have forgotten it," he said, "They may still make life choices because of it."