You never know what the person beside, in front, or behind you is going through.

Just smile

You never know if they just lost a lover, a friend, family member, or a pet.

Just smile

You never know if they just lost their job.

Just smile

You never know if they just lost all their savings.

Just smile

You never know if they just found a new lover, friend, family member, or pet.

Just smile

You never know if they just got a new job.

Just smile

You never know if they just won the lottery (and are looking for genuine people to share it with).

And finally:

Just smile

You never know when someone will lose you.