JOHNSON COUNTY (CBSDFW.COM) – Child Protective Services is now investigating the death of a girl just outside of Cleburne, although police continue to classify the tragedy as an accident.

The parents of Lilly Parsons reported the four-year-old missing around 7 p.m. Monday night.

“The parents noticed that the child, who had been outside had disappeared and they made a quick search and then they called 911,” said Lt. Tim Jones with the Johnson County Sheriff’s Department.

When police arrived at the home they searched for the 4-year-old girl and soon found her in the back of an SUV, parked in the driveway  in the 1200 block of Westlake Road.

Authorities say they still don’t know how Lilly died. “The time of death and the actual cause of death is unknown at this time, pending the medical examiner’s report,” said Jones.

After her body was discovered, officers spent hours looking through the SUV for evidence. Temperatures hovered around 100 degrees on Monday evening. It’s not clear if heat was a factor in the death.

“All indications are this was an accident,” Jones said. “We want to remind people not to leave your children in the car, or elderly people in the car, not saying that’s what happened by any means, but it’s way too hot, you have to be careful.”

Marissa Gonzales, with Child Protective Services says their investigation has begun and the family has no prior history with CPS.

“We don’t have a cause of death yet so we’re not sure what caused this child’s fatality,” Gonzales said. “That’s part of the investigation, interviewing everyone, figuring out what the timeline was and what may have happened.”

Three other children live at the house. All of the kids, an 8-year-old, 6-year-old and an infant, remain in the home with the parents, and other family members.

Now, as the family tries to cope with the loss of a child, the community is pulling together to help in any way they can.

“I just took them lunch today, and introduced them to one of our counselors at church,” said neighbor Brent Easdon, “It’s just the Christian thing to do.”