So here we go, for the last time--the answers to these clues are two children's books.
1. I somehow missed this series, though it looks like my kids could have read it. I don't think they did--at least, I know I didn't read it to them. I had to go to good old Wikipedia to figure out a possible clue. So here it is: I didn't read these books, but I did read--or at least I have a copy of--the two volume set of Le Mort d'Arthur from my college days. Unless Wikipedia lies, there's some connection there.
2. I'm not sure if I read this book by this author or not, but if I did, it wasn't a favorite. I do, however, have two copies of a slim book he co-authored.