Two-year-old Sophie Jones suffered a deadly cardiac arrest on Tuesday night, after her mother allegedly had given the toddler a heroin substitute to clam her down.
The lethal dose of the drug, Methadone, which is normally prescribed to drug addicts, reportedly belonged to one of her family members
The police alleges that Sophie was given a drink laced with the drug; the residue from the mug is being examined by toxicology experts.
In connection with the girl's death her 29-year-old mother and a 41-year-old man were arrested.
The investigation is not finished yet, the local detective claims there still may be many possibilities, "all of which are being explored."