Mark Five: The Last Question
Nudge. It is Morse code: each group of dots and dashes is one letter. Look the alphabet up.
Harder
In Morse, dot dash dash dot is P and a single dot is E. Read the other three groups the same way.
The answer
The word is peace.
In Morse, dot dash dash dot is P, dot is E, dot dash is A, dash dot dash dot is C, and dot is E: PEACE. It is Kit's answer to anyone who tells his father he is in the house.