HAMBURG, N.Y. — It’s estimated that one in five students between 12 and 18 will experience bullying at school. With many schools now in summer break, students could be spending more time on their phones.

That’s something Deanna Gresko is warning against.

Her daughter, Nadiya Santiago, was a shining light in Gresko’s life.

“She was an 11-year-old. Typical happy kid,” she said. “She liked her friends. She did good in school. She loved her sports.”

Nadiya’s mother had recently gotten her a phone for good grades.

“She said, ‘I accidentally posted a video on TikTok, and I’m embarrassed,’ ” Gresko recalled. “It was a cute little — I don’t know — you do them little dances, you know? It was super cute. She looks super cute in it. And I go, ‘there’s nothing wrong with it.’ She goes, ‘Mom, I’m embarrassed.’ She’s like, ‘can I stay home tomorrow?’ And I’m like, ‘yeah.’ ”

That next day, Gresko left Nadiya at home alone while she picked up her other kids.

“I gave her a hug and a kiss, and I said, ‘I love you,’ ” recalled Gresko. “That was the last time I saw her.”

Nadiya died by suicide. Gresko says there were no signs she was going through a hard time, apart from what happened with the video.

She says it’s something parents need to keep an eye out for.

“You really need to monitor what they’re doing, because this could be you sitting here telling you your story about your child,” she said. “It’s not worth it for a phone.”

During summer vacation, students are away from potential in-person bullies. Cyber-bullying can persist.

“It can be really hard because things can spread really fast online,” explained Stephanie Fredrick, the associate director for the Alberti Center for Bullying Abuse Prevention. “Things can be shared and liked and things like that.”

But Frederick notes that because cyberbullying usually reflects in-person bullying, it can slow in summer.

“Some of those social gatherings, the football games, all of that, that’s not happening,” she said. “Also during the summer, I think there’s greater choice for young people on who they spend their time with […] and that’s really powerful for peers, and a really big protective factor actually against bullying.”

She recommends parents watch out for uncharacteristic behaviors that last more than a week or two and have open dialogues with kids about what they’re doing online.

“As opposed to like, ‘why do you spend all that time on your phone? It’s rotting your brain.’ You know, we don’t want to have kind of that disapproving attitude, but instead asking questions, [and] co-using devices with our kids,” Frederick said.

But, there aren’t always signs someone’s in crisis.

“These are things people wrote about her,” said Gresko, opening a box of consolation notes from Nadiya’s schoolmates.

For Nadiya’s family, it’s a hole that won’t ever be filled.

“This is the worst pain that a mother or father or sibling could ever feel,” she said. “I wouldn’t wish this on my worst enemy.”

She hopes parents emphasize more time away from the screen and always provide that safe space.

“I have so many children reaching out to me saying that they’re in the same predicament as Nadiya and nobody will listen to them,” she said. “We need to give them hope, and we need to just let them know there’s people out there that will that will help them.”