Woah. I found a paradym

so, I was fatefully watching tv the other day, when the football game ended and all of the sudden a show popped on that both presented thought provoking questions but also displayed a paradym shift. The subjuct of this was laughter.

Now the paradym shift that they briefly mentioned was that laughter used to be interpreted as evilness, so laughing was rarly heard. People laughing was not displayed in portraits painting all through this time. I did not catch the time period but the Mona Lisa was one of the solemn picture that was used as evidence of this, as they flashed through them. I found this rather interesting.

The pondering question was that there was this couple who lived a very sad life, and did not laugh (apparently, i don't understand how this was possible) yet they had a baby and around two months old, this baby started to laugh. The question for him was where did this baby learn to laugh. There was studies done on babies blind, deaf, and with lack of proper sensation and all the babies started to laugh at around the same age as the babies who lived with out these conditions. So the questioned remains, is laughter just instictual and as we grow older some people decide to stop doing it? Should we allow stress or pressure distract us from doing something inate from birth?
I just found it interesting.