Answer:
temperaments.
Step-by-step explanation:
When we speak of temperament, we refer to that innate part of our personality that is determined by our genetic heritage. Therefore, it is considered the biological and instinctive dimension of personality. In fact, temperament is the first personality factor to manifest.
In babies it is already possible to distinguish different types of temperament. Thus, depending on their tendency to feel and express positive or negative emotions and a good or bad mood, it is possible to consider them children as "easier" or "difficult" in behavioral terms. As you can see from the question above, Jonah is a baby with an easier temperament, while Irene is a baby with a difficult temperament.