High school senior, 17, killed just days before graduating by lightning strike as she sat writing in park.

Jennie Dizon of Downers Grove dropped off her two younger siblings at the dentist's office Thursday, part of an afternoon of errands she was running for her mom.

Not wanting to wait around at the office, the artsy, expressive teenager went to nearby O'Brien Park to write in her notebook, something her sister said she did frequently to journal about her thoughts and feelings.

It was around that time that authorities say the 17-year-old Benet Academy senior apparently was struck and killed by lightning.

"She didn't answer her phone," sister Emmeline Dizon said Friday. "We just kept calling and calling and she didn't answer."

On Friday, her grief-stricken family tried to come to terms with how the bubbly, vibrant teen, three days away from graduating high school, could suddenly be gone.

"Jennie is our angel," said her mother, Marietta Dizon. "She has a golden heart. Whoever has met her, she has surely touched your heart. I think God had called her. We just have to place our whole trust in him."

Police called to the park near 68th Street and Dunham Road in the western suburb about 5:20 p.m. Thursday found Jennie on the ground, unconscious and not breathing, authorities said.

She was pronounced dead at the scene a short time later, and an autopsy Friday determined the cause to be electrocution due to a lightning strike, according to the DuPage County coroner's office.

Officials at Benet Academy in neighboring Lisle, where Jennie attended school with Emmeline, 16, expressed their heartbreak in an online statement.

"Throughout the day her close friends, classmates, teachers, and the entire school community have had opportunities to recall her many talents, her unique gifts, and her wonderful personality," the statement said.

"Though she was taken from us much too soon, we trust that she is now in God's loving embrace."

Dizon's death was not yet reflected in National Weather Service data, which track the number of fatalities caused by lightning strikes in the U.S. To date the agency has recorded five deaths in 2013, below the historical average of nine through the first five months of the year.

Police said Jennie appeared to be alone at the time of the strike, and there were no witnesses.

"A resident who lives by the park heard a loud lightning strike," Downers Grove police Lt. Mike Willison said. "He looked out and saw a person lying in the park, so he called us and we responded."

Emmeline and her brother Michael, 14, saw police in the park, , just across from their two-story brick house, as they walked home from the dentist. But they didn't find out until later what had happened to their sister.

"They say you go through the stages of grief," Emmeline said. "I felt like I went through all of it at the same time. Now it's all coming around again and I'm in a stage of denial."

Arielle Joaquin and her sister, Issa, were in a Catholic youth group with Jennie and Emmeline. Arielle Joaquin described Jennie as an eccentric and loving girl who loved wearing bright clothes and eye shadow and had a laugh that carried down a hallway. The teen also enjoyed singing and playing the ukulele and piano.

"She loved everyone, and there was never any chance of her hiding it," said Arielle Joaquin, 22. "She looks exactly the way that she is on the inside. You could see the love that she had in all that she did."

A sign commemorating Jennie's impending graduation stood just outside the family's home Friday. Her mother said that celebration was to be just the beginning of her daughter's hectic summer, which was to include a trip to Europe with classmates and a cotillion for her 18th birthday in June. Then she was to attend the University of Cincinnati to study theater production.

"Those are great things, but we know she's in God's hands now," Marietta Dizon said.

A wake for Jennie will be held from 3 p.m. to 9 p.m. Sunday and Monday at Hallowell & James Funeral Home in Downers Grove. A funeral Mass will be celebrated at 10 a.m. Tuesday at St. Scholastica Church in Woodridge.

As her father stood in his driveway, he rued the milestones he would not experience with Jennie.

"I was looking forward to our father-daughter dance at the cotillion," Eric Dizon said. "She was supposed to graduate this Sunday. She graduated from life, I guess."