There are over 50 books on my bookshelf by a single author - Enid Blyton.
What surprises me about this vast collection is that none of them are remnants from my own childhood or from my latter collection of children's books - though I read them all in the day. They are all the product of my own children, voracious and early readers, discovering them and being addicted to them and wanting to have them on the shelf ready for another read. Many are accessible from a young age while some still appeal to the older reader. However they all have something in common, they are gripping and reward multiple readings.
I know Enid Blyton is sometimes out of favour with critics and educators, but she had a gift for writing and the evidence is on my shelf. Her books persist in publication because they are popular and that popularity hasn't waned, at least in my house.