What is the essence of the negative signals Da-duh signaled at the beginning of the story?

The second we are introduced to Da-duh by the granddaughter, we learn that Da-duh is in charge and the matriarch of the family. Da-duh’s daughter and granddaughters approach her apprehensively fearing her hypercritical nature. Da-duh immediately judges them and sizes them up before ever really talking to them. 

We see Da-duh’s influence on her own daughter when the daughter’s hand tightens around the hand of Da-duh’s granddaughter, and she approaches Da-duh very formally.  The granddaughter...

The second we are introduced to Da-duh by the granddaughter, we learn that Da-duh is in charge and the matriarch of the family. Da-duh’s daughter and granddaughters approach her apprehensively fearing her hypercritical nature. Da-duh immediately judges them and sizes them up before ever really talking to them. 

We see Da-duh’s influence on her own daughter when the daughter’s hand tightens around the hand of Da-duh’s granddaughter, and she approaches Da-duh very formally.  The granddaughter notices that her mother has “suddenly with a word been reduced to my status.”  Da-duh also sums up the other granddaughter when she says she will be lucky in life because she is of “lighter skin.”  Da-duh’s impression of her other granddaughter (the narrator) is that she has a “fierce” look about her, something we learn is characteristic of Da-duh as well. Da-duh’s lack of a loving greeting and her judgmental nature gives off a negative and powerful presence.

Da-duh’s physical description also gives us insight into her negative aura.  The granddaughter describes her face as, “stark and fleshless as a death mask . . . only the framework of bone beneath the ruined skin and deep wells at the temple and jaw. But her eyes were alive, unnervingly so for one so old.”

Da-duh's negativity shows she is a formidable figure not only in appearance but also in her attitude.  Her family fears her and shows her the respect she demands. She is not a loving mother (despite having 14 children), and she is critical of those around her who don’t live her way of life in Barbados. It is only the granddaughter who challenges Da-duh’s power in the story.