At an infant care center, 6-month-old dexter begins to cry. hearing dexter, 7-month-old kristina starts crying as well. before long, several other infants add to the chorus. this situation illustrates:

This situation illustrates emotional contagion.
This means that among infants, emotions are contagious - so if one child starts crying, it will 'contaminate' other infants with its feelings, and then all of them will start crying in chorus, sharing the same feelings even though they might not feel sad or the need to cry at all.