Editor's note: This story was originally published in July 2012, after the mass shooting in Aurora, Colorado. Questions about grief and loss are coming up again this week as families cope with the aftermath of explosions in Boston.
(CNN) -- Of the 12 people killed in the July 2012 mass shooting at a Colorado movie theater, 6-year-old Veronica Moser-Sullivan was the youngest.
Long after the moments of silence have ended, people around the country will still be at a loss for words to describe what happened to the fathers, mothers, sisters, brothers, daughters and sons killed and wounded.
Those close to the victims have an especially difficult task: finding words of solace for the incomprehensible.
Grief experts say the loss of a child brings on a special kind of anguish.
"You think about all the things you'll miss: the graduations, the swim lessons, the dance recitals," says Patricia Loder, the executive director of The Compassionate Friends, a foundation that supports those who are dealing with the grief that follows the death of a child.
Loder lost her two children in a car crash in 1991 and has since channeled her grief into helping others.
"One of the most important things is to listen to what the parents have to say. I call it 'the head and the heart.' Their head knows their child has died, but their heart doesn't want to believe it," says Loder.
CNN's photo gallery of the Aurora shooting victims prompted many commenters to share opinions on what to say and what not to say when talking to bereaved parents:
CNN commenter "Nellen" said: "When you want to comfort a parent whose child has died, please don't say 'I can't imagine...' I don't know why, but when people say this, and I hear people on air saying it all the time, it upsets me. My son died 2 years ago, and the way I interpret those words might seem skewed, but I can't help it. I hear those words as saying: 'That could never happen to me' or 'You are so different from me I can't relate' ... "
CNN commenter "sallyforth88" responded: "When people, who are trying to comfort someone, say things like, 'I can't imagine,' they really, probably CAN'T imagine because it's never happened to them. Would you rather have someone say to you, 'I know what you must be feeling?' I find saying something like that is 10 times worse. But they are just trying to comfort you. Please don't be so sensitive when people are only trying to help ... some people don't know what in the heck to say."
Sometimes it's not what you say, it's what you don't say, according to psychiatrist Abigail Brenner.
"The best thing to do is be around and listen to the parents, and try not to inject your own opinion," says Brenner. "Inevitably most people have never lost a child, so saying 'I know how you feel' is not going to help."
Even if you have lost a child, Brenner says the phrase "I know how you feel" is too subjective: every parent's response is different. Some people try to make the best of it; some people fall apart; some people get angry; some people try and channel it into something positive.
"They think they must say something. We're a society where we're uncomfortable with silence. We think we need to put a reason why this happened out there," says Loder.
Sometimes just being present is the best thing you can do. Let the parents know you're there for them: pass them a tissue, rub their back, allow their tears fall onto your shoulder.
"You don't have to say a lot or try to take the pain away. Words like 'I am so sorry' or 'I am here for you' can be healing. It's important to acknowledge their pain and not change the subject or tell them it's not so bad," says clinical psychologist Melanie Greenberg, who specializes in grief and trauma.
And while it's easy to try to find that proverbial silver lining or light at the end of the tunnel, Brenner says comments such as "this will pass" should be avoided, because while the grief may pass, the memories of the child won't -- and shouldn't.
"The whole idea of finishing grief doesn't mean you stop mourning a child or you get over it, but the thing is you have to have closure on the emotional life. You carry the memory. You want to be able to move on."
Please share the words and actions that have helped you through traumatic events in the comments section below.