Timothy Sullivan died from multiple blunt force injuries by manner of homicide, said Coroner Meredith Buck.
“Our office extends its deepest condolences to the infant’s family and friends during this difficult time as they grieve this unimaginable loss," she added.
Bristol police were called to the 1000 block of Radcliffe Street for an infant in cardiac arrest late on May 24, Daily Voice reported. When they arrived, Sullivan was "not breathing and cold to the touch."
Officers performed life-saving measures but eventually took the baby to Lower Bucks Hospital, where he was pronounced dead just after midnight.
Medical staff at the hospital said the boy was already dead when he arrived, and that his injuries were "indicative of a battered child" — he suffered "contusions, bruising, and abrasions" throughout his body, the DA's Office has said.
Investigators believe the boy's father, 30-year-old Tyler Sullivan, "violently shook" his son at least two times on May 24, and "at least six additional times" in as many weeks.
The elder Sullivan has been charged with homicide and two counts of aggravated assault. Court records show the 30-year-old is awaiting his formal arraignment on Aug. 25.
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