What may the father’s portrait, as mentioned in the fifth paragraph, represent? Does the narrator mention about the portrait anywhere else in the story? If yes, in what ways could this be significant?

THe little we know about her father illustrates a domineering unforgiving disciplinarian. He was cruel and stifled his daughter's attempts to assert herself in any way. Some critics feel the portrait was done by Emily herself.

Once Emily failed miserably at life, she turned back to her father's tortured ideal for her which is perhaps the only comfort she recognizes hence the painting. I don't recall it literally mentioned again but I'll have to check.