I've just discovered that my story Liquid Skin gets an honourable mention from Ellen Datlows Year's Best Fantasy & Horror from its appearance in Quercus One - the West Pier Gazette. Yay!
So, I'd say that there are several stories in this collection I wouldn't really consider to be aimed at children. Horror, you know, being sort of a key word here. But because I've gone for a whimsical title, and the book has a pretty cover, it's turning up in catalogs as a "Children's Book".
Never been my intention, nor that of the publisher, to market it as such, and if you give this to an eight year old there will be snot and nightmares.
My brother read it and passed it on to the teenage nephews, and they've read it without apparent permanent damage (teenage boys, how can you tell?) so not suitable for younger children would probably be a guide.