Hi, I am also from Australia. Our daughter had a h on the bridge of her nose. We were told by pead's and derms that it would go away, but even the pead said that she may require surgery before she went to school because of deep component would probably leave fatty tissue behind. I sent some photo's to Dr Reinisch in LA and he advised the same thing, re the fatty tissue and suggested having the surgery earlier than 5. We travelled to the US and had the surgery done when she was 4.5 months old. It was great, the best decision we ever made.. It really was a 'procedure', surgery sounds too harsh. She was just an outpatient and surgery was about 1hr, and recovery about 1hr, she wasn't even in pain when she woke up, we just gave her some panadol just in case, and she was perfect, never even touched the site...
I am impressed you found someone in Australia who will do the surgery.. Of course it is completely up to you and your family to make the decision, wishing you all the best.