Answer:
The important detail that should be added to this summary is "The author’s father left the family with nothing."
Step-by-step explanation:
This summary of "The Rights to the Streets of Memphis.” by Richard Wright need to include the detail that triggers all the following events, that the author's father abandons them and left them without any money or security, sets the new kind of life that each one of them will have to deal with to survive without him and his income.