The government uses a set of words that do not follow the same English grammar rules that the rest of us ordinary people use. Australia has a Governor General, which is the general governor for the whole country. Because it is an important government post (answering to the Queen) the wrong word order is used. Today I will explain why this is done and when we have to use the wrong word order.
In English, adjectives (describing words) are usually placed before the noun (person, place or thing) they describe. In French, the adjective is usually placed after the noun. For example:
English: Tom has a red book.
French: Tom a un livre rouge. (Tom has a book red.)
This problem comes from the time that England was ruled by Norman French speakers who had invaded in 1066. Afterwards the government spoke French and the farmers spoke English. Many English language problems were caused by this situation. This French-speaking colonial government often translated orders into English words, but kept the French word order. Today governments often still follow French, not English, grammar rules for some adjectives. The result is structures like father in-law which are called post-positive adjectives. The adjective in-law is placed after the noun father.
Even today, in Hong Kong, the police might talk about "persons unknown" instead of unknown people, for example:
The joint charge alleges that between January 1, 2013 and July 26, 2016, the 18 defendants conspired together and with other persons unknown to defraud...
ICAC press release 11/15/2017
Post-positive adjectives are common in government, law, titles, coats of arms and ancestry-relationships, all matters important to a French colonial ruling class. Using this structure for ordinary purposes will sound either wrong or pretentious. Some of these terms still require a French accent.