As nouns the difference between childishness and childlikeness
is that childishness is (uncountable) the state or characteristic of being childish while childlikeness is the state or quality of being childlike.
childishness
English
Noun
(uncountable) The state or characteristic of being childish.
(countable) Childish behaviour.
See also
* puerilism
* puerility
childlikeness
English
Noun
(-)
The state or quality of being childlike.