Panel 1: We find ourselves watching Marian remind us that Lynn has a distorted vision of how real estate works when she tells Elly that their place has been on the market for only two weeks and they've received an awful lot of calls already.
Panel 2:She then says that they'll be ready to move to the condo in July but will have to sell a lot of things.
Panel 3: When she asks Elly if there's anything she'd like to have, Elly wants to be 'polite' and say that she's never really thought about it.
Panel 4: She then thought-bubbles that she wants the rocking chair, the glass lamp, her grandma's sewing kit, the tea chest and the old pump organ. Since Marian cannot read thought bubbles over the phone, this means that Elly will eventually scream in pain because her thoughtless mother cannot read her alleged mind.
Summary: At no point in the discussion do Jim or Marian ever learn that Elly and Phil see the pump organ as a prize for Best And Most Beloved Child. They die not knowing this.