What does the cake symbolize in "A Small Good Thing"?

Ann Weiss, Scotty’s mother, orders a cake for his birthday from the local baker. The cake is a chocolate cake and is to be “decorated with a spaceship and launching pad under a sprinkling of white stars, and a planet made of red frosting at the other end.” Also, his name is to be added to the cake “in green letters beneath the planet.” Mrs. Weiss places the order for the cake on a Saturday afternoon. She hopes to be able to pick up the cake on Monday morning, in time for Scotty’s birthday later in the afternoon.
Scotty has an accident on Monday, the morning of his birthday, while going to school with his friend. A car hits him at an intersection. He does not appear badly hurt but walks back home to tell his mother about it. After talking to his mother, he lies on the sofa and “goes limp.” He is taken to the hospital, where he is diagnosed with a “mild concussion and shock.” However, he remains limp for the duration of his hospital stay, about three days, and finally dies. His death is attributed to a “hidden occlusion.”
Talk of the cake features at the beginning of the story, when Scotty’s mother visits the baker to order it. Next, the cake is mentioned when Scotty’s father gets back home from the hospital on the evening of Scotty’s birthday. He is just in time to receive a phone call from the baker reminding them about the uncollected chocolate cake. Scotty’s father does not know about the cake that had been ordered for his son’s birthday, so he does not understand what the caller is talking about. Also, he has had many disturbing issues to deal with during the day, so a cake is the last thing on his mind. He is not in the best of moods to understand the caller. On the other hand, the baker is a man of few words. He does not take his time to explain what he is talking about. The call ends without a meaningful exchange of information between the two people. Afterward, the baker calls frequently. Whenever somebody does pick up his call, the two parties are unable to understand each other. The Weisses are going through a difficult time with Scotty in hospital. Even Mrs. Weiss is unable to remember that Scotty’s birthday cake is lying uncollected at the baker’s. After Scotty’s death, the Weisses return back home and receive the last call from the baker, a little before midnight. Suddenly, Ann remembers the uncollected birthday cake and concludes that the caller could most likely be the baker. She and her husband pay a visit to the baker, who they think is “mean and a bastard” for harassing them with inane calls in the dead of the night.The cake is a symbol of the day of Scotty’s birth. The three-day-old cake that lies at the baker’s shop is a symbol of death, as it is “getting stale,” just like a lifeless body. Also, the cake is the cause of the persistent calls that the Weisses receive from the baker. Thus, it brings the reader back to the lack of understanding between the Weisses and the baker. It draws attention to the need for proper communication between the baker and the Weisses over the unresolved issue of the uncollected cake. It is through the uncollected cake that the Weisses connect with the reserved baker. When they visit his shop to complain about his incessant calls, they stay the rest of the night, talking to him and “they do not think of leaving.”