EVANSTON, Ill. (CBS) — Just hours into summer break, a 16-year-old Wilmette girl made a fatal mistake while hanging with a friend on the CTA Purple Line tracks – and now she is dead.

Samantha Cerrone, a New Trier High School student, was electrocuted while walking on the tracks in north Evanston, not far from the Wilmette line, around 2:30 a.m. Thursday.

READ MORE: Chicago Police Officer Released From Hospital After Being Shot In Shopping Center Parking Lot At North And Sheffield Avenues

On Thursday night, her dad told CBS 2’s Charlie De Mar he had always been worried about those tracks. And he said if there is any way to honor his daughter, it would be to pay attention and adhere to warning signs – and stay off the tracks.

(Credit: Cerrone Family)

Cerrone was on the swim team at New Trier.

“She enjoyed being a part of this program. She enjoyed being with her friends here,” said New Trier Aquatics Coach Greg Hartman. “This was her happy place.”

Hartman, Cerrone’s swimming coach, will never forget Lane 4 at the Wilmette pool where she practiced.

“This pool is where Samantha took her last strokes,” Hartman said. “Her last start was off of Lane 4. Her best friend was behind her. They were jovial. They were laughing. They were cracking jokes.”

The 16-year-old finished her sophomore year at New Trier this week.

(Credit: Cerrone Family)

Evanston police said overnight, she was out walking with a friend along the Chicago Transit Authority Purple Line tracks just north of the Central Street station. Cerrone tripped and fell onto the electrified third rail.

READ MORE: Chicago Weather: Pleasant Parade Weather Tuesday

She was rushed to NorthShore University HealthSystem Evanston Hospital, where she later died.

The tracks at that location are at grade-level rather than elevated, and Evanston police said that is how Cerrone and her friend were able to get on easily.

“Just as we’re getting, it seems, on the other side of a pandemic, we are saddled with a truly tragic accident,” Hartman said.

The friend with Cerrone tried pulling her off the tracks. She also suffered an electric shock, but is expected to be OK.

On Thursday night, flowers covered a memorial – along with heartfelt messages left behind from classmates.

The Cerrone family describes Samantha as an advocate for others.

Her obituary reads in part, “She lived to not be ordinary and encouraged others to have the confidence to do the same.”

“This is a parent’s worst nightmare,” Hartman said. “This is a coach’s worst nightmare.”

Cerrone’s family lives just blocks from where this happened. Her father did not want to go on camera, but he said from a young age, he warned his daughter about the dangers of trains.

MORE NEWS: Indiana Attorney General Files Lawsuit To Crack Down On Harassing Robocalls, And Effort May Help In Illinois Too

Funeral services are set for this weekend.

Charlie De Mar