MIAMI (AP) — A child welfare investigator didn’t notice that a 5-month-old baby now presumed dead was missing after visiting the family’s South Florida home in September, according to documents released late Monday.

The investigator only checked on the older children in the home and did not see the baby, according to documents released by the Department of Children and Families. A month later, Brittney Sierra told police she hadn’t seen her baby in more than a year.

Remains that are believed to belong to missing five-month old Dontrelle Melvin were unearthed Friday in the backyard of the parents’ former home. Twenty-one year-old Sierra and the baby’s father, Calvin Melvin, are not married and have an on and off relationship.

The two have been charged with child neglect. The medical examiner is conducting DNA tests to identify the remains.

A child welfare investigator went to Sierra’s home in September after someone complained to the state abuse hotline that the children were dirty and smelled and that Sierra’s younger sister brought a pornographic magazine to school after taking it from her father.

Officials said Sierra and her two other children live with her mother and Sierra’s four younger siblings.

The investigator also visited the children at school, interviewed them and determined there were no signs of abuse or neglect, only that the house did smell a bit. The children said they were fed and well cared for, according to records released by the Department of Children and Families.

But the “younger children were not seen,” according to the report, including five-month old Dontrelle.

The agency has been criticized over several cases in recent years in which investigators and caseworkers claimed they visited a home, but really did not or did not make contact with all of the children living in the home.

An investigator following up on a 2011 call that Nubia Barahona was in danger did not make contact with the girl when she visited the family’s home and didn’t call police. The 10-year-old’s body was found days later, decomposing in the back of her adoptive father’s pick-up truck. Records released after her death indicated several red flags after calls to the state hotline that the child smelled and had bruises.

In Dontrelle Melvin’s case, records also indicate the agency had 30 prior contacts with the family.

In 2011, a caller complained that several of the children were riding a city bus alone to school each morning, but are picked up in the afternoon by their mother.

Another hotline call last week prompted the investigation that eventually led to the discovery of the remains. That caller told hotline operators that people in the home smoked drugs in front of the children and that a two-year-old was running down the road naked and without shoes.

The unidentified caller said the mother’s boyfriends are always around the house and that one hits the children, according to the call.

“So many of them running in and out of the house over those kids and smoking drugs and drinking and all of that stuff over the kids,” the caller said.

An investigator visited the home after that and asked where baby Dontrelle was. The father said the baby had been living with his parents about 20 minutes away, but they said that was untrue. When investigators went back to Melvin’s home, he had disappeared. He went to the police station last week to be interviewed and was later arrested. Police said he has changed his story several times and at one point said he dropped the child off at a fire station.

Meanwhile, DCF has taken the baby’s two siblings into custody and four of Sierra’s younger siblings.

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