Kevin Byrne and his wife, Kim, talked to their daughter Alyssa about drugs. But all the heart-to-heart talks didn't save her.
The 19-year-old was found dead in a South Lake Tahoe snow bank with drugs in her system after leaving the Snow Globe Music Festival.
"We learned the hard way," he said. "You need to know what your kid is into."
Alyssa's death sparked a year of activism for the Byrnes, starting with the Always Buddy campaign.
"It's so crucial if you're going to a new place or going to a party," Kim said. "It's crucial you go as a group and come back as a group."
At last weekend's concert, event-goers took the pledge. Volunteers set up a warming station and drove the streets picking up young people who walked away from the party just like Alyssa did.
A message about the dangers of drugs is also spreading around Petaluma, Alyssa's hometown.
Kevin said kids are reaching out to him for help. He has taken some kids to meetings and helped them talk to their parents -- time consuming work he and his wife plan to continue in honor of their daughter.
"I think right now she's looking down and she's saying it's amazing all this started," Byrne said. "Another part of her is saying why does it take something as tragic as this for this to happen."