Carol meets andy and brad outside of her psychology classroom. both young men smile at her, but when brad smiles, he used only h
is mouth, whereas andy also has crinkles in the corner of his eyes. carol feels that only andy is genuinely happy to see her because andy has displayed a, whereas brad has used a
Andy displays a Duchenne smile which is believed to be the true smile of happiness while Brad has used a fake smile because it did not involve his eyes but he only smiles using his mouth.
The primary function of the family is to ensure the continuation of society, both biologically through procreation, and socially through socialization. Given these functions, the nature of one's role in the family changes over time.
