Well it was a near miracle that we all got together in the first place without a war between the colonies. None of the colonies liked the other, all were in competition in regards to markets & so forth, some where expansionists wanting to start their own empire, whilst others were protectionists & paranoid of their neighbours.
Then, for Federation, states argued over were the capital would be. Then, when Melbourne became the temporary capital, Sydney demanded & got the official Residencies of the Prime Minister & Governor-General. Even today, even though the national capital moved to Canberra 80 years ago, Sydney still has the official Residencies of the Prime Minister & Governor-General. Then there were arguements over railway gauges, arguments over taxation, arguments over industrial relations, arguments over defence, etc, etc, etc...
One big happy family