Australia's first appearance was in "Good to See You Australia," in which he swung by Scandinavia on the way home from visiting England. He is on friendly terms with all three of them. Denmark thinks he's sexy (of course) and Sweden invites him to his dinner parties.
As England's son, Australia has at least six siblings: Sister Australia, the America siblings, the Canada siblings, and little Sealand. New Zealand, originally a family pet, is his neighbor, and her daughter New South Wales is one of Australia's states. His extended family includes Scotland, Wales, and Ireland. He gets on reasonably well with his family members, though sibling rivalry with both America and New Zealand is not out of the question, and England is still ready to believe that he's been up to no good.
The World Edit
Australia appears to be in early adulthood. He has tan skin and shoulder-length blond hair, and the portrait-style pictures reveal him to have blue eyes and a wiry build. He wears a tank top with the design of the Australian flag, dark brown pants, a utility belt on which he carries a knife and other gear, and a brown armband.