If you grew up in Australia in the 1980s and '90s, chances are a large part of your sex education came from one book.

Where Did I Come From? was first released in the UK in 1973 but it took another couple of years before it arrived in Australia.

By then, its author Peter Mayle had quit his day job as an advertising agency creative director to write full-time off the back of the success of what was his first book .

Innocent question that sparked an idea

The book was written by British-born Peter Mayle, who reportedly came up with the idea for the book after being asked a question by his son.

According to The Conversation , there are two versions of the story of how he came up with the idea for the book.

The first is that his son asked him how babies were made,

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