Hi Eyad what is FLA and SLA ?
Behaviorism is a little bit outdated in psychology, do they still teach it in your country? Now there is cognitivism which puts the accent on how a person thinks about himself and the world in which he is living.
Regarding the phrase you mention “ a child is born with a blank slate” it isn’t considered accurate anymore. Human babies are far more competent than scientists believed in the 60 ties.
Babies still in the womb of their mother are able to discriminate sounds. They recognize the voice of their mother and other close people . Fetuses usually accelerate their heart rhythm when they hear something familiar.
But Skinner was right, the baby must be stimulated to learn a language. If like Mowgly he lives among wolves he will not learn any human language. But it is more complex than a mere stimulus/ response.
Anyway it is a good topic.
In the 1970s, a colleague of mine was about to become a father for the first time. We had many spirited discussions on nature versus nurture, the tabula rasa, and whether all behavior was learned. He was a psychologist, and in those days, psychology in the US was very much in the tradition of John Watson and B. F. Skinner. I was a software engineer... with some background in ethology, the study of animal behavior from the point of view of evolutionary biology.
I said to him "Our experience is that babies have personalities and individual characteristics from day one, which they could not have possibly learned. You are about to have your first child. Tell me in a year what you think."
To his credit, some time later, he said "You're right. Anyone whose raised a baby has to believe they arrive with some pre-existing, unlearned behavior hard-wired in."
(I'd add that it is even more obvious after you have had two children... each with a definite, different personality from day one.)