There are several material objects that serve as symbols in ‘night, Mother. Two important ones are the candy that Thelma Cates prefers to eat and the cocoa that Jessie prepares for her and her mother to drink. The gun also serves as a symbol.
Thelma has spent much of her life trying to avoid facts and unpleasantness. She has withheld information from her daughter, including information regarding Jessie’s epilepsy, in an effort to make things seem less serious. She has sugarcoated life’s negative aspects. Her ingestion of candy and her stated intention to live on sweets if Jessie dies are manifestations of this unrealistic attitude toward reality. Similarly, Jessie prepares cocoa, allegedly a treat for them to share. However, neither woman likes milk, so it is not something they would normally share. She tries to mislead her mother into believing they have things in common, symbolizing their distinct world views.
Although the gun is an important object within the plot as the instrument of Jessie’s suicide, it is also an important symbol because it is her father’s gun. Jessie is not sure of its location, so she asks her mother about it. This precipitates a discussion about her intentions, which causes Thelma to divulge important information about the father. Revealing the hidden gun stands for revealing the hidden information.