After weeks of treatment for severe burns, Landaverry died late Tuesday at Temple University Hospital. She was preceded in death by her mother, Olga Galdamez, who succumbed Sunday morning to her injuries from the July 1 explosion.
"We're all really shocked," said a tearful Yasmin Landaverry, Jaylin's cousin. "The doctors were saying Jaylin would recover, and then she got worse again."
As word spread yesterday of Jaylin's death, the staff at Little Flower High School, where the teen was a rising senior, scrambled to organize a prayer vigil.
Hours later, in the waning heat of the day, the school's gym, on Lycoming Street near 10th in Hunting Park, was packed wall-to-wall with Jaylin's friends and teachers.
"She was so genuine, so humble," said Pamela Espinoza, who met Jaylin when they took Spanish together as freshmen. "It's still so surreal; I just can't believe this."
Espinoza and Jaylin grew close while working together on Las Flores, the school's spirit club, which organizes pep rallies and other functions.
Jaylin didn't have "a lot of free time," according to Espinoza - she spent nearly every minute outside of school helping her mom run the family business.
"It was the ticket to their future, that truck," said Carol Dauerbach, who taught theology to Jaylin.
"They worked hard, and they struggled, but they did it joyfully," said Dauerbach, who added that Galdamez often awoke at 3 a.m. to prepare her cuisine, all for the chance to keep her daughter in the school she loved so dearly.
"She was happy, and she had such a desire to be here at Little Flower," said Dauerbach.
The theology teacher's voice cracked as she recalled writing a letter of recommendation for Jaylin, who aspired to attend medical school and to become an ob-gyn.
After the prayer service in the gym, the attendees trekked to 4th Street and Wyoming Avenue, where the memorial was placed.
"We felt the need to put this symbol down," said Sister Donna Shallo, president of Little Flower.
As Shallo watched Jaylin's friends light candles and pray, she shared her own memories of a "sweet, hard-working young woman" who called Little Flower her second home.
"I'm comforted in knowing that for the last few months, she was where she wanted to be."