because smile makes you young..actually there is a social meaning in Filipino smile.
...it keeps us from giving up, makes us prevail.
... smile is an expression of strength in the face of frustrations and hopelessness. But it’s not just muscles flexed in the mouth. And not necessarily an expression of happiness. But it could mean to say that, jointly with the one you’re smiling at, you’d bear it out with him.
A smile could mean, “It’s all right, don’t worry.”
Or “I’m so sorry….” in an apology. (Smile)
Or “Gosh!” shyly. (Smile)