(CBS News) CHICAGO - President Obama made one of the most impassioned speeches of his presidency on Wednesday when he called for action to end gun violence.
But as strong as his words were, no one can make the case as powerfully as a family that's been victimized by a criminal with a gun.
It was May 10, 2007. A surveillance tape captured a teenager with a gun boarding a Chicago bus -- and shooting.
"A crowded bus full of teenagers and people coming home from work. He shoots five kids that day, five teenagers, and my son died as a result of that," Annette Nance-Holt said.
Nance-Holt's only child, Blair, was 16. More than 2,300 people have been killed by guns in Chicago in the years that followed.
"I think a lot of people are indifferent because they figure it didn't happen to them or they figure most of our kids in our community are gang-bangers or drug-dealers or don't go to school, they're uneducated, they don't have fathers or they don't have mothers. I think a lot of people look at us like that. And that's not true. When my son was murdered, I got a letter in the mail. It was a week later. Somebody found out where I live. They mailed me a letter. It said had somebody on the bus been armed, if everybody on the bus had a gun, my son would be alive. No! I think a lot of people on the bus would be dead today," Nance-Holt said.
Following her son's death, Nance-Holt co-founded "Purpose Over Pain" -- an organization that advocates for gun control. Last week, she met with Vice President Biden's task force on gun violence.
"The mothers and fathers who've lost their children to violence have to raise up and say something now. I know it's hard to stand up, but we all have to stand up and give our voices," Nance-Holt said.
Nance-Holt said she felt like the NRA hasn't helped in the fight against gun violence so far.
"I would say they need to come up with some common sense plan to how we can combat gun violence. It's not getting more guns. That's not a common sense plan to a mother like me or to other families in the city of Chicago who've lost their children to violence," Nancy-Holt said.
For those who believe it could never happen to their family, Annette Nance-Holt said she once felt that way too.