First sparks, usually accompanied by thick grey smoke, appear at around six months.
-- excerpt from Dragon Breeding for Pleasure and Profit (DrBr)
Rowling shared small portions of her notes on her original website as rewards for solving puzzles. One of the rewards was an illustration she drew showing a collage of pages from the book Dragon Breeding for Pleasure and Profit: 
												Other canon
Dragon Breeding illustration
		Dragon Breeding illustration
AuthorJ.K. Rowling
										Publication May 15, 2004
				Abbreviation DrBr: Dragon Breeding for Pleasure and Profit
		Canonicity Secondary Canon
	Commentary
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