AMNA NAWAZ: It's been two months since at least 135 people were killed when flash floods roared through the Texas Hill Country.

Last night, state lawmakers passed the first round of legislation in response.

The bills, which focus on improving camp safety, faced opposition from some Texas camps, who said the new safety requirements would put them out of business.

But among those killed at Camp Mystic during the July 4 floods was 8-year-old Virginia Hollis.

I spoke with her Parents, Lacey and Lars Hollis, yesterday ahead of those votes.

LARS HOLLIS, Father of Virginia Hollis: It's a very challenging time for our family.

Sleep is very hard to come by.

AMNA NAWAZ: Weeks after losing their first-born daughter, Lacey and Lars Hollis remain haunted by the night that flooding claimed her life and 26 others at Camp Mystic.

LARS HOLLIS: What these sweet little girls had to go through that evening is just very painful.

And we're taking it day by day.

AMNA NAWAZ: Eight-year-old Virginia, big sister to Siena, was spending her first summer at the camp on the banks of the Guadalupe River.

LACEY HOLLIS, Mother of Virginia Hollis: She was so excited to play her -- for the talent show at camp, to get to play for the piano song that she composed.

She was like: "Mommy, I bet nobody else who's 8 has a piano song that they have written themselves."

Thinking about, just as a little girl of 8, how brave and strong she could be playing piano for strangers just because she wanted to share music with them, at least, for me personally, it's really given me the strength to testify, to drive to Austin, to meet with people and tell them about her and why this is important.

AMNA NAWAZ: On July 4, storms pounded the Texas Hill Country.

Some 550 campers were at Camp Mystic, many asleep in cabins in high-risk flood zones.

The National Weather Service reportedly sent a severe flood alert at 1.14 a.m. Campers weren't evacuated until at least 2:00 a.m. LARS HOLLIS: No child should be sleeping in a floodplain.

Detection, we're an incredibly advanced civilization, and we need backup redundancy with our technology when there's thousands of lives at stake.

Training.

Camp is wonderful and fun, but just like most places we send our children, there has to be training.

Know what to do in the event of an emergency, know where to go, not in a shelter in place in a flood, but where are we all going?

And the campers and the counselors need that type of training at camps.

LACEY HOLLIS: These things that we thought were in place because they're in place in our schools, they're in place everywhere that has the care of children, except apparently summer camps.

She was 8.

She was barely 50 pounds.

I think she was 48 pounds.

And her sweet 18-year-old counselors, they did their best.

I know they did.

I know they did everything they could.

AMNA NAWAZ: Virginia's body was found more than a week after the floods.

Hundreds in her hometown of Bellville, Texas, lined the streets to say goodbye.

LACEY HOLLIS: My daughter Virginia, our first child, named for me and for my grandmother, died some time after the rain and river flooding that happened in the early morning hours of July 4.

We don't know when she died.

We don't know how.

We really don't know anything.

We may never know.

AMNA NAWAZ: Lacey and Lars turned their pain into purpose, just 47 days after Virginia was killed testifying before a Texas Senate committee.

LACEY HOLLIS: My anguish is as infinite as the stars in the sky and equally as unfathomable, searing, blazing, exploding, a black hole of pain.

AMNA NAWAZ: Watching you both testify before the Texas Senate, I was in awe of your strength and your grace.

And it really stuck with me, Lars, when you chose to play a clip of a piano song that Virginia wrote, she composed herself.

It's called "Virginia's Song."

You said it was the last song she ever composed, and you played it so everyone could hear.

(MUSIC) AMNA NAWAZ: And I just wondered why, why you wanted people to hear that song.

LARS HOLLIS: A wise person once said, when someone you love becomes a memory, that memory becomes a treasure.

And I believe that was a treasure that Virginia left us all and was a gift that we could all enjoy.

And I felt compelled to share it with the world.

LACEY HOLLIS: For me, hearing her song sometimes is difficult, because she was working on other compositions.

She just never got to finish them.

And she wanted so badly to be a composer and a pianist and also a cowgirl, a teacher and a mom.

But it just really brought home to me, like, every single one of them had wonderful things to share with the world.

And all of those things were snatched away from them and from the world.

And I'm so grateful that we have that song, but also part of my heart breaks for all the other songs that -- all the music that died with her.

And it's just like it's just one little snapshot of what we're missing for the rest of our lives.

LARS HOLLIS: It's a challenge, but that's what -- we're here today to advocate on behalf of these 27 beautiful souls that needlessly lost their life.

And we want to ensure that there's not a 28th child next summer.

STATE REP. DREW DARBY (R-TX): We have got folks in the audience whose girls died at Camp Mystic.

Thank you for your patience.

This bill has been expedited less than two months from the date of the occurrence because we want to make sure that another camper, another child will not go to sleep subject to the horrors that you have had to endure.

With that, members, I urge passage.

STATE.

REP. DUSTIN BURROWS (R-TX): A hundred and twenty-two ayes and eight nays.

Senate Bill 1 passes to third reading.

AMNA NAWAZ: Their message was heard.

Hours after we spoke, Texas legislators passed Senate Bill 1, known as the Heaven's 27 Camp Safety Act.

Among other things, the act will ban camp cabins within 1,000 feet of a floodway border, require camps to prepare to evacuate after a National Weather Service flood warning, and require evacuation routes be displayed in youth camp cabins.

Another bill, House Bill 1, also passed last night, requiring overnight kids camps to develop emergency plans and submit them to the state.

Both bills head to Governor Greg Abbott to sign into law.

LACEY HOLLIS: I, for one, have that hope that that will be what happens and that there won't be a 28th child that suffers a preventable death at a Texas camp in the future because there wasn't enough preparation, there wasn't enough training, that there wasn't a big enough or the right response, that there wasn't detection.

That won't -- I have that hope now.