40 Never believe a crying boy and a laughing girl 2

Chrystal really did feel confused by the connection which emotion had with health. After a few considerations, she remembered herself studying that when a person is physically healthy, they would feel mentally happy but when the person seems to be physically sick, they would have to face some mental pressures like depression, fear anxiety unsure of their life. Hence it had some connections.

But that was physical and mental then how about the emotion? How does sadness have an effect on health? She was totally confused about it. Chrystal Zhu gave it some rest and closed her eyes to sleep. The weather was perfect as it was so cold, it made her feel sleepy easily.