There has not been a single death attributed to an overdose of cannabis - it is completely non-toxic. That means that it is not possible, even for a child, to consume a fatal dose of the herb.
Known drug-related deaths in the UK, 1990
Tobacco: .................110,000
Alcohol: ..................30,000
Volatile Substances: 112
Morphine: ................91
Methadone: ..............84
Heroin: ....................62
Barbiturate Type: ....7
Anti-depressants: ....4
Cocaine: .................4
Pethidine: ...............3
MDMA (ecstasy): ...3
Amphetamine Type: .2
Hallucinogens:........ 0
LSD:....................... 0
Psylocibin:............. 0
Cannabis: ...............0