When a loved one commits suicide, families are often in a state of shock -- and also unsure about whether they should speak about the cause of death.

The "Out of the Darkness" walk in Philadelphia Sunday offers those touched by suicide a way to remember their loved ones, and to spread the word about suicide prevention.

More than 2,000 people have signed up for the walk, including Catherine Siciliano who lost her son, Anthony, to suicide in 2008.

Siciliano is also a board member of the American Foundation for Suicide Prevention, which organizes the annual event. The walk is a great support, especially to those newly bereaved, she said.

"It's a community of healing, where everyone there knows what they are feeling, what they are going through," she said, "the complicated grief that one experiences through that loss."

And, she said, it's a way to get people talking about a deadly taboo topic.

"We're losing our loved ones in silence," she said. "We need to unmask that silence, we need to break that stigma, and this is where it starts."

Education is key in preventing suicides, Siciliano said.

"We need to educate, we need to let people know what are the signs, what should I look for, especially kids," she explained. "We're not giving our kids the tools they need to identify that 'hey my friend seems really sad,' or 'she is not acting herself' and know when it's OK to reach out for help."

Garden Wellington, who lost her brother to suicide, will be among the walkers. She says awareness is key since suicide can be prevented sometimes with very small interventions.

"Survivors often tell you, it was just one phone call, one hug, one more push, that they needed not to do it," she said. "That's really hard to hear for somebody who lost somebody to suicide, because we always think 'What could I have done differently?'

"However, we can't look back," Wellington said. "We have to look forward, through our walk, our education, every program that we have."

The money raised by the walkers goes to awareness campaigns, as well as support for people touched by suicide. The national suicide hotline can be reached by calling 1-800-273-TALK.