It's hard for children's authors to be accepted when they try to write adult books. J.K. Rowling is the exception because people are so eager to read anything by her, but it took Judy Blume three or four tries before she had a success.
Many adults feel that every children's book has to teach them something.... My theory is a children's book... can be just for fun.
I feel that good fantasy will always be in demand. I think children especially need literature that helps them escape from the real world, which is very scary to them right now.