"W" & "V"

[Abu Taybah]

There was a couple, husband's name was "ST" & wife was called "SU". They didn't have a child.
Someone told "SU" that if you drink water & stay inside a dark room with a small window open for ventilation, you will have a wonderful child that will bring benefits to mankind. And you should name the child "V".
 
"SU" drank water & stayed inside a dark room, but a mistake done by her was that she forgot to open a small window for ventilation, so she gave birth to a child...... called "W" instead of "V". But unfortunately, the child "W" could not bring benefit, rather "W" brought losses, diseases, disaster & evils.
 
"W" liked to stay in dark, in an anaerobic environment, the same conditions it received during development.

Next time, "SU" drank water, stayed in a dark room & opened a small window & she gave birth to "V".
"V" was absolutely opposite to "W", it proved of benefit to mankind, it brought happiness, health, blessings & goodness.
One day, "SU" took "W" outside in open air, & she observed that "W" started changing its habits similar to that of "V".
But "W" changing to "V" in an aerobic environment never competed characteristics of "V" that was brought up aerobically.

My question is : Who are "W" & "V" ?