Tom needs to find a suitable guardian for Eddie, just in case something happens to him. Tom and Helen's list of relatives is relatively short from which to choose. Helen's sister, Kate, is unsuitable since she is constantly traveling. Helen's parent's are too elderly. That leaves Tom's mother. Eddie doesn't really know his grandmother all that well as she lives in San Francisco, and doesn't visit all that often. So Tom thinks it's a good idea to bring his Mom to Los Angeles for a visit, although he doesn't tell her or Eddie the reason. Tom's mother is formal, stern and judgmental, she who views anyone who does not have the same values as her as a Communist. Eddie doesn't really like her as she makes him feel "flat". Tom ultimately doesn't believe that she would make a suitable guardian for Eddie. He next thinks that Mrs. Livingston the ideal candidate: she and Eddie mutually love each other and Mrs. Livingston would probably accept the responsibility. However Mrs. Livingston thinks that she is not the ideal person, as because Eddie and Tom have eked out a certain lifestyle, what Eddie would need is another father figure. Although reluctant since he doesn't consider himself to be either father material or stable, Norman is Tom's final choice. Since Eddie and Norman also mutually love each other and ultimately Norman would have Eddie's - and Tom's - best interest at heart, Norman accepts.
—Huggo