The death of a two-year-old boy in Ipswich last week is being investigated as murder, according to Suffolk police.
Kamari Russell died alongside his 19-year-old mum Kia Russell at a house on Swinburne Road on Wednesday evening.
Post-mortem examinations have found both died as a result of compression of the neck.
While the infant's death is being investigated as murder, Suffolk Constabulary say they are not treating Ms Russell's death as suspicious.
A police statement said: "Detectives do not believe that there is anyone else directly involved with this incident and the investigation into the deaths continues."
A 17-year-old boy was arrested shortly after the deaths, though not on suspicion of murder or manslaughter. He has since been bailed to return to police at 10am on the 29th March.
The police statement added: "Anyone with information about this incident is asked to contact Suffolk Constabulary on 101 quoting 37/12929/19."