Lambert was at a friend's house, and a loaded gun was on the kitchen table. Lambert's friend, who was also 14 at the time, thought the gun wasn't loaded and pulled the trigger.
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"What happened to Adrienne was a tragedy and we don't want it to happen to any more children," Lambert's mother, Marentha Sargent, said. "You have to teach your kids to go tell an adult when they see something that's not right. Don't pick up a gun even if you think it's not loaded. Even if you think it's a toy. If it's not yours, don't touch it."
Sargent spoke to ABC13 Eyewitness News for the first time Wednesday about the end of the long legal process that sent her daughter's shooter to juvenile detention.
The shooter's father, Charles Roessler, was sentenced to 30 days in jail, while the shooter's mother, Kathy Roessler, pleaded guilty to making a firearm accessible to a child. Kathy was sentenced to community service.
SEE MORE: Man sentenced after leaving loaded gun around son leads to accidental shooting of 14-year-old girl in Deer Park
"We feel a sense of relief," said Sargent. "But it doesn't bring Adrienne back. But we're glad that it's all over with, and we can just start to heal."
As part of that healing, Sargent now has a tattoo of her daughter's face on her arm. It's a work in progress, like her grief.
"I want people to ask me so that I can tell them about her," she said. "That can lead into us talking about guns and gun safety."
Eyewitness News spoke with Kathy on the phone Wednesday, and she said that the incident was a severe tragedy, but declined to speak more about it.
"We always said that she was just too soft for this world," said Sargent. "But I don't think that's what it is. I think that she was here for a reason, and maybe her reason was to help other families."
Kathy will begin serving her sentence on July 13. Instead of serving her time in the Harris County Jail, she will perform her community service for Harris County from 7 a.m. until 3 p.m.
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