Published: Jan 15, 2013 11:31 AM EST

MIAMI (AP) - A child welfare investigator didn't notice that a 5-month old baby who is now presumed dead was missing after visiting the family's South Florida home in September.
    
According to documents released Monday, the investigator only checked on the older children in the home and did not see the baby. 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 Dontrelle Melvin were unearthed Friday in the backyard of the home where the parents once lived.
    
Sierra and the baby's father, Calvin Melvin, are not married and have an on and off relationship. They've been charged with child neglect.
    
The medical examiner is conducting DNA tests to identify the remains.

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