In the UK, one is permitted to have dual nationality by [but not limited to] jus sanguinis, to obtain citizenship if at least one of the child's parents have citizenship in the UK.
This is also permitted in Australia, given that one has an Australian citizen parent at the time of one's birth and if that parent is an Australian citizen by descent and has lived in Australia for at least two years...
So, if I am not mistaken, the child can indeed be granted dual nationality.