Answer: Interactionism
Explanation: Interactionism is a concept of human interaction or relationship such as friendship, talking and all sorts of behavioral actions between two or more people which drives or contributes to an individual's knowledge, understanding or thought of social processes such as conflict, relationship, cooperation and so on.
Informal Interactionism could be learnt by a child through observation of his parent and how they relate or interact, quarrel management, and other issues.