Contagion

‘Emotional contagion' is the tendency to express and feel emotions that are similar to and influenced by those of others. Emotional contagion may be involved in mob psychology crowd behaviors, like collective fear, disgust, or moral outrage, but also emotional interactions in smaller groups such as work negotiation, teaching and persuasion/propaganda contexts. It is also the phenomenon when a person (especially a child) appears distressed because another person is distressed, or happy because they are happy. The ability to transfer moods appears to be innate in humans.