They say their son makes friends more easily and is learning to better control his reactions.
Music therapy, often done alongside other therapies, extends this idea to help the healing and personal growth of those with identified emotional, intellectual, physical or social needs.
"Music therapy is a relationship between the therapist and client - a therapeutic intervention which uses music as a tool," says Clulee.
New Zealand is celebrating its first Music Therapy Week starting today. The aim is to celebrate and develop greater public awareness and understanding of the therapy.
Fifty-two registered music therapists work in early-intervention centres, hospitals, schools, prisons, rest homes, rehabilitation units and private homes.
Clients include children with special and additional educational needs, adults with learning disabilities, children, adolescent and adults with mental health issues, those undergoing rehabilitation via ACC and the elderly.
It is paid for through a variety of methods, including Ministry of Education and the Ministry of Health funding when appropriate.
It has been found to help those with dementia because music can help unlock memories, manage stress-induced agitation and emotions, aid general brain function and reduce isolation.
The University of Auckland's Centre for Brain Research helps run the CeleBRation Choir, a social singing group for people with neurological conditions such as Parkinson's disease.
The breathing and vocal exercises done in the choir help maintain vocal function and research shows singing may help to "rewire" the brain after an injury.
On Tuesday, the centre will host the music therapy symposium Singing Together: Celebrating Music Therapy and Musical Partnerships. It includes a range of presentations, looking at developments in music therapy, and a performance by the CeleBRation Choir.
Since 2004, a Master of Music Therapy training course has been available through Massey University and now Victoria University.