When adult children divorce, struggle financially, abuse drugs, or have similar life problems, it can have a major impact on their parents' mental health and satisfaction, according to a study presented today at the annual meeting of the American Psychological Association, in San Diego.

CNN: When adult children fail, parents suffer too

Dr Mathew White and colleagues at the European Centre for the Environment and Human Health found that individuals reported less mental distress and higher life satisfaction when they were living in greener areas.

BBC: Green spaces boosts wellbeing of urban dwellers - study

To me and my understanding , humor may works tremendously as an anti-dote to mental aberration caused by tough competition dis-satisfaction and contending situation at every step in life.

FORBES: 10 Reasons Why Humor Is A Key To Success At Work