Level of Emotion, Need & Capability are different at different Ages
The role, duties, responsibilities, behavior, conduct and expectations are different for the above four stages in the life of humans.
The other classification is childhood, adolescence(teenage), adulthood, middle age, retirement and old age. In these six stages of life, progressively the human beings evolve in terms of intellectual capacity, experience, spiritual attainment and enlightenment.
However, the youth energy vigour and risk taking capacity decreases progressively as physical and physiological capacities deteriorate progressively post retirement.
The need and capability
Every human being have to deal with the other human being. Whether as friend, relation, family, etc. And behave accordingly as per their emotions and fulfill as per their needs and expect from them as per their capabilities. But, sometimes without understanding of their capabilities, emotions and need, we try to deal with them which causes unnecessary stress and unfruitful results.
As per Law of Nature, the emotions, needs, capabilities, of a human being are different at different ages / stages of life and hence we should deal or interact accordingly.