5 March 2018 - Naomi Taylor and Ben McLennan watch their son William deteriorate every day.
He has type two spinal muscular atrophy - a cruel, degenerative disease with no cure.
But in a remarkable breakthrough there is now a drug available that has seen some astounding results.
The drug, nusinersen sodium (brand name Spinraza), has been approved for use in Australia, but was rejected for listing on the PBS last year.