This was not a simple question because different people might have different understandings and usages of the word " childish." In some cases, it might be considered childish for girls to cry while reading novels because it might be seen as a girl's over-reliance on emotional and emotional expressions or an over-interpretation of the plot and characters. However, in other situations, girls crying while reading a novel may be considered a sign of emotional maturity, because it shows that girls have rich emotional experience and imagination and can get emotional resonance from novels. We can't make a general assumption that it's childish for girls to cry when they read novels because it involves different people's understanding and views on emotions and emotional expressions. It was important for girls to learn to express their feelings and feelings independently and not to feel guilty or uneasy because they were overly dependent on others.