There were lots of favourites I and my sisters had when we were children, but it's only the ones for somewhat higher ages that I actually recall titles and authors of, for the most part... and of course some of them probably don't exist in English, and for the ones that do I don't necessarily know the title.

Still, some of our favourite picture books back then that I'm fairly sure are either originally English-language or available in English include the books by Shirley Hughes, Posy Simmonds (The Chocolate Wedding is brilliant), Peter Spier, Violeta Denou, Dieter Schubert and Chizuko Kuratomi (took me some real detective work to track that last one down, though - as far as clues to go off on go, "those Japanese books about that bear" is not, as it turns out, very helpful). And Raymond Briggs' The Snowman (although perhaps the animated movie version is even better, since it has that music).

For somewhat older ages, Roald Dahl is obviously a must, Enid Blyton for those who wouldn't find her too old-fashioned, Monica Furlong (Wise Child cannot be praised enough), Gillian Cross (The Demon Headmaster is a classic), Astrid Lindgren, Rosemary Sutcliff (historical fiction), Anthony Horowitz (mostly horror or at least rather scary stuff), and many more I'm sure.

And then for young teenagers, 10-14 or so, I'm a big fan of William Bell (Forbidden City, particularly) and Aidan Chambers, both writers with an impressive ability to write about and for teenagers without patronizing them. There's also S.E. Hinton's The Outsiders, a masterpiece when you consider she wrote it aged 16. And here too, many more I'm sure.