"A Raisin in the Sun"-Something Wrong

Throughout the entirety of Hansberry's play, I was pondering why the characters's moods were not more solemn.  Why were they not sad?  Assuming the death was not too long ago because they are just now receiving the insurance check, the audience wonders why the family would not resurrect his memory more often and focus on the man rather on what the man left them.  Through the trials of the times, they (with the exception of Mama) lose sight of why they are getting the money in the first place: the death of the father.  The man, who is referred to as extremely hard-working, is little remembered for who he was rather for what he left in monetary terms.  The greedy attitudes, especially those of Beneatha (for her education) and Walter, present a foreign sentiment to the play.  Most surprisingly is the fact that they do not even seem to notice what they are doing: forgetting their father and his legacy in the search for financial security.  Asagai must point this out for Beneatha.  "Then isn't there something wrong in a house --in a world--where all dreams, good or bad, must depend on the death of a man? (Hansberry, 135).  In this, the audience learns that money is not this family's problem, it is the way they have chosen to lead their lives because of money that is the problem.