Canadian researchers set to study cannabis oil
23 February 2017 Last updated at 02:23 GMT
Liam has Dravet syndrome, a severe form of epilepsy. But after debilitating seizures and pharmaceutical trials and errors throughout his life, Liam's parents turned to cannabis oil.
Now a Canadian hospital in Toronto will be studying the effects cannabis oil in a new study - as many doctors are worried about prescribing it without scientific data on dosage and potential side effects.
Video by Dan Lytwyn