fiction - What is considered "childish" in fictional writing?

There are some people who have read some of my book so far and they think it is childish and then some say it's somewhat morbid.

What are your views on what each of those terms means?

Answer

It could be any number of things given that we've seen no excerpt (although sharing one may not be advisable, since advice specific to your case wouldn't help this thread's future users). I'll mention some possibilities; other answers will probably add some more. Some of my examples are things writers find more appropriate when writing for children; others are bad writing people may associate with stories aimed at children, if for these the publication standards are more lax.

• The vocabulary may be basic.


• The sentence structure may be repetitive or undemanding.


• The punctuation may be unsubtle (I've seen stories in children's annuals where just about every sentence ends in an exclamation point, weakening them all).


• The characterisation may be 1-dimensional, may be riddled with a straightforward allegory (viz. The Chronicles of Narnia), or may tell instead of showing.


• The dialogue tags may also do this, through synonyms for "said" or modifications of it with adverbs.


• The repetition in sentences or word choice may grate (see e.g. here).


• The themes or treatment thereof may be all too innocent.