The state Department of Children and Families erred last year in returning a Lynn infant and his twin brother – born with drugs in their system -- back to their mother, a report released Friday said.

The Office of the Child Advocate released a report about the death of 3-month-old Chase Gideika, who was found “bruised and not breathing” at his home in July of last year.

His mother’s boyfriend, Anthony Gideika, has been charged in the alleged killing. His mother, Jennifer Nelson, also was indicted for reckless endangerment of a child.

Gideika is one of a growing number of substance-exposed children born in Massachusetts. The New England Center for Investigative Reporting wrote a story about the state’s troubles in protecting these medically fragile infants who are born with opiates in their system and often suffer severe withdrawal symptoms at birth.

They include Mya Barry, a 5-month-old who died in 2011 after allegedly ingesting heroin from a milk bottle given to her at home. The report said the state needs more resources to protect these vulnerable children and their at-risk families. It also said DCF should focus more resources toward protecting children over keeping troubled families together.

For more information, read the Boston Globe’s story here.