GM

You have set out to cross the forbidden woods. At the crossroads before the entrance to the woods, an old man approaches. "Don't go in here, it's not safe"

-He seems to mean it guys! What does your character say to him? Quickly, he's walking away!

Player (how it is here):

-The old man is my father.

"Hi father, what have you seen?"

Normally a GM would say 'no he's not your father'. A player should ask the GM whether his character knows the old man (actually the player should assume the character doesn't know the man, because the GM would have said so if that was the case).