Parents of Alfie and Harry McQuillan describe what happened when they discovered the overdose of morphine had been given.
One twin was given ten times the recommended dose while the other twin was given 17 times the normal dose.
Both died soon after the drug was given.
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England and Notts County Ladies goalkeeper Carly Telford will launch a campaign later today to encourage women to get involved with sport.
Isolated showers will largely die away, and winds will decrease. Feeling chilly with clear spells.
Any early showers will die away leaving most of the evening and night dry with clear spells.