Bonding and Resonance
When we witness emotional cues in those we are close to, such as
facial expressions, body language or vocal intonation, our own physiology
may resonate with theirs, creating an approximation of their physiological
state within our body. Emotional resonance is especially strong between
a parent and child. A parent may actually feel their child's pain,
as well as their joy.
It is said that the act of smiling precedes the feeling of happiness.
When we smile in response to a smile, happiness is shared.