Sophia Bush Discusses Her Cousin, Arizona Shooting Victim Christina Green

'It's been a lesson more than anything for me and for my family that life is incredibly short,' 'One Tree Hill' star says.

Sophia Bush sat down with Chelsea Handler on her E! talk show, "Chelsea Lately," on Monday night, and while much of the conversation was lighthearted in nature, the "One Tree Hill" star also took time to remember her young cousin, 9-year-old Christina Green. Green was killed in Arizona over the weekend when a gunman attacked U.S. Rep. Gabrielle Giffords and others outside a Tucson supermarket.

"It's been a lesson more than anything for me and for my family that life is incredibly short. You've gotta take every day and tell the people you love that you do. It's really important for all of us to take a step back," she said. "It's easy to get heated and to scream and yell about what's going on in the world, but when it's getting irresponsible, when it's getting out of control in the world of journalism and television ..."

Handler weighed in on the tragedy too, saying, "Anything that incites any sort of violence ... I'm the biggest bully there is. I make fun of everybody ... But you can't ever, ever suggest violence."

Bush also expressed her sadness over the incident on Twitter, writing, "There are no words to explain what my cousin's family is going through in Arizona. How can this be? Violence is never the answer." Bush also encouraged anyone who knows somebody struggling with mental illness to lend a hand. "If you know anyone who is struggling, please reach out to them," she added. "No one should feel so alone that they resort to senseless violence."

Congresswoman Giffords remains in the hospital, and her doctor, Michael Lemole, said that he is encouraged by her progress. "There is no change, and as frustrating as that may sound, that's a good thing," the doctor, who is the head of neurosurgery at the University Medical Center in Tucson, told NBC's the "Today" show.