Wednesday's Child (1970) is a prequel to this episode, showing Shirley's life with the Nourses; Shirley was played by Prunella Ransome.
Incidental music includes "Hello World" by The Tremeloes and "Up, Up And Away" by The 5th Dimension.
In the opening shot of Frank sitting at the breakfast table, there are two ceramic jars on the shelf behind him. One of them has the word "COCAINE" written on it.