I figured, nothing beats wishing those whom you care and/or you love, a "Good Morning" greeting, to start their (and of course yours as well) day on the right and high/optimistc note.
Even if you know the day will be a tiring one, and sometimes when you anticipated to have things not going your way, I believe, to a certain extent, a greeting message every morning/afternoon/night is a good reminder to those around you, that theres a bright side to everything, and to make them remember to always keep their morale high, because we need them to fight the upcoming battle.
Press on!
Jean