Sudden infant death syndrome (SIDS), also known as cot death or crib death, is the sudden unexplained death of a child less than one year of age. Diagnosis requires that the death remains unexplained even after a thorough autopsy and detailed death scene investigation. SIDS usually occurs during sleep. Typically death occurs between the hours of 00:00 and 09:00. There is usually no evidence of struggle and no noise produced.