A homeless family of four, including a young boy and girl, who had been sleeping inside a van at a Garden Grove shopping center’s parking lot were found dead inside their makeshift home, possibly victims of carbon monoxide poisoning, authorities said Friday.

“We don’t want to roll up on scene like this, let alone where a family died,” said Garden Grove police Lt. Carl Whitney, standing just a few feet from an empty parking space littered with soiled diapers and paper cups, where the van had been parked hours earlier. “They could have been sheltered.”

The gruesome scene came to light around 8:30 p.m. Thursday when a woman walking though the lot outside a CVS pharmacy at 12031 Brookhurst St. noticed a foul odor coming from a white Honda van.

Called to the scene to investigate a suspicious vehicle, police officers found inside the van the decomposing body of a man, possibly in his late 30’s or early 40’s; his wife, who appeared to be in her 20’s; their son, who is about 9-months-old and daughter, who is nearly 2, Whitney said.

The father was identified as Phunyouphone Kanyavong, 41, the GGPD announced on Friday afternoon – the mother and children would take longer to identify, they said.

The family, who are from the Garden Grove area and have relatives nearby, appeared to have been sleeping in the van. They likely had been dead about three days before being found, the lieutenant said.

The van was parked right next to a grass median, which possibly obstructed the exhaust system and may have caused lethal levels of carbon monoxide to fill the vehicle, according to Whitney. Police announced in an update that there were no signs of trauma or foul play. On Friday evening, police were awaiting the results of a toxicology to confirm the cause of death.

When officers arrived, the van’s windows were covered with blankets and a sunscreen. Its engine wasn’t running.

Dan Walbon, 64, of Anaheim, who was homeless until recently, said he was acquainted with the family, who apparently had been living in the van for about six months.

The family split their time living in the CVS lot or at nearby Hare School Park, where they hunted for bottles and aluminum cans that could be recycled for cash.

“I tried to help them out with food,” he added. “The kids kind of looked like they were undernourished.”

The deaths, including those of two young children, left some of the transients who congregate in the parking lot distraught and questioning what else might have been done.

“It’s sad for the family and bad for the kids,” Walbon said. “They didn’t have a chance at life.”

To those who work closely with homeless families, the deaths underscored what they say is all too common: Parents without homes who have underage children often don’t seek help because they worry their children will be removed from their custody. Or they encounter long waits to access limited resources.

“It’s a challenge for the general population to understand or imagine a family to be homeless or living in a vehicle,” said Elizabeth Andrade, director of Family Solutions Collaborative, 11 agencies that work together to provide a more welcoming and comprehensive point of entry for homeless families needing services. “Unfortunately, it takes a tragedy like this to highlight that.”

Andrade said there are 450 families on a list with the county’s Coordinated Entry System who are considered homeless and waiting for some sort of housing: Some are in shelters, some with motel stays paid for by social service groups, others living out of their vehicles.

“Who knows how many haven’t come forward, haven’t been assessed, are back and forth with friends and family, or are paying for their own motels?” Andrade said.

Next to the parking space, a makeshift memorial of candles and flowers stood on Friday afternoon. A handwritten sign resting against a tree read,” It’s time to love and pray for the homeless. God Bless this family. It’s time to help as a community.”

Garden Grove police responded to about 4,000 calls for service involving transients in 2007, but its two officers assigned full-time to deal with the homeless never encountered the family, Whitney said.

Had the man and woman approached police they likely could have received shelter quickly because of their young children, he said.

“Orange County has a lot resources but the homeless have to be willing to accept services,” he said.

In Orange County, there are a total of 120 units of emergency shelter for families with children, offering stays that can range from 30 days to about six months, depending on the program, Andrade said.

Families found to be living in vehicles typically have been doing so routinely, not for just one or two nights, Andrade added.

“They’re there,” she said. “They’re just scared to expose themselves.”

Anyone with information about the incident is asked to contact Garden Grove police at 714-741-5704.