i and my husband are staying in Gold Coast, QLD and going to get the citizenship after 1.5 yrs. We would go back HK to "earn money" and let the kid to study in HK until 10 yr-old. My son is now 1.5 yr old. We have observed lots of HK migrates' case and we found that if kid can study primary school in HK, the chinese level is pretty good. Meanwhile, if he comes back australia before adolescence (i.e. boy is about 11 yr-old), he can adapts the new enviornment better, also with good english ascents, good social skills with other australian kids...etc