Yes, it is very normal for toddlers to experience strong emotional reactions to storybooks, even those that seem mild to adults. They are often developing a deeper sense of empathy and a desire to explore emotional boundaries. If your child insists on reading these specific books despite the tears, try validating their feelings, skipping or simplifying the 'sad' pages if possible, or gently pivoting to a book with a more positive narrative after the initial story is finished.