A behavioural paediatrician is a great step for a 16 month old. I took Matilda first to the Mater Children's in Brisbane which does multi-disciplinary assessing. I waited 18 months to get in though... so if you are going public, be prepared to wait a while. For multi-disciplinary they are assessed by an audiologist, a speech pathologist, a physiotherapist, a paediatrician and an occupational therapist. With those results they get together and make a diagnosis or suggestions on where to next. With Matilda, the suggestion was to see a psychologist and decide if it was behavioural or ASD. She has Sensory Integration Disorder which was diagnosed at that time as well. 88% of kids on the Autistic spectrum have Sensory Processing issues.

I see you are Nth West Melbourne? I know that Maz has said they have amazing services in Shepparton, so maybe ask her about something close by?