It's been 25 years since 12 students and one teacher were killed in the Columbine

massacre in Littleton, Colorado. It was the largest mass killing at a high school

in US history at the time. Since then, overall school shootings have grown to much higher levels,

and there have been several mass shootings with tragic losses at schools like Sandy Hook, Parkland, and Uvaldi.

Tom Mauser lost his son Daniel. Sandy Hook, Parkland, and Yuvaldi.

Tom Mauser lost his son Daniel at Columbine that day,

and he joins me now.

Tom, welcome to the news hour.

Thank you for joining us.

Thank you.

So 25 years, when you say it can feel like a very long time and maybe not that much time at all, I hope

you don't mind if I just begin by asking, how are you doing? You know doing well, you know, there's healing, some healing

comes with with time. It doesn't seem like 25 years to me, frankly. Why is that?

I really can't explain it.

I mean, for one thing, to me, Daniel is still 15.

I don't think of him what he would be doing today or what he'd be like.

He's still 15.

And you have dedicated your life and your days to honoring Daniel,

to doing what you can, to end gun violence.

You've been traveling around the country and talking to people

tell me a little bit about that work what's that journey been like and what have you

learned along the way well you know I've met a number of other people who have

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