Fairfield police have yet to release the girl's name or officially the cause of death, but Monday at the school where she was last seen last Thursday, her fellow students know exactly who they lost.
Students at Fairfield's Green Valley Middle School say it was a tough day, the first day back after they learned one of their classmates, a seventh grade girl, was found dead in a city park.
"She was really nice to people and she always hugged, like, a lot of us," student Jordan Carrow said.
"She was known a lot, everyone pretty much knew her," student Frankie Torres said.
Police did not release any new details Monday, three days after the 13-year-old's naked body was found in an open area at Allan Witt Park in downtown Fairfield. Investigators canvassed the area around the park over the weekend searching for witnesses. In the meantime, a small memorial has cropped up in the park near where the girl's body was found.
The girl was living in a foster home at the time of the disappearance. It was her foster parents who called police to report her missing Thursday afternoon.
"She was at a good environment at the house, that's all I know," Cheryl Parrish said.
Parrish says she lived in the same home with the same foster parents until last summer.
"They're worried, scared, probably miserable; it breaks their heart, as much as it does mine," she said.
"The foster mother is very loving, kind, she's very protective," Fairfield resident Roshawn Forrest said.
Contacted by ABC7 News, a spokesperson for the agency that placed the girl in the Suisun City foster home said, "Our thoughts and prayers are with anyone who knew this young lady and we will certainly cooperate in any way we can to find those responsible."
Parents at Green Valley Middle School say the murder has prompted some conversations with their kids.
"Just keep an eye out, stick together; even if you're walking down after school, stay together, watch out for each other," parent J.C. McKelvey said.
School officials are planning to address this girl's death with some kind of assembly later this week.
Investigators are still asking anyone with information to contact Fairfield police.