As part of his motif of the hardships of orphans, along with Pip, Biddy has also lost her parents and kept by Mr. Wopsle's great-aunt, who is her grandmother. But, like Mrs. Joe, Biddy's great aunt brings her "up by hand" and uses her granddaughter to arrange the transactions in the little general shop that she owns. A bright, energetic girl, Biddy teaches Pip his letters and to read and to figure while he attends the great-aunt's school.
A sweet child and unselfish child, Biddy, who displays a great concern for whatever Pip does, becomes his confidante. Not realizing that Biddy loves him, Pip tells her of his amorous feelings for Estella, his hopes for the future. When he leaves to go to London and follow his "great expectations," Biddy asks Pip if she and Joe might walk a little farther with him. Pip kisses her, promising to tell her everything as they part. However, once Pip arrives in London and begins to put on the airs of a gentleman, he forsakes the loving friend, Biddy.
Soon, though, Biddy becomes the housekeeper for Joe and Mrs. Joe, who has been attacked and is in poor condition. On behalf of Joe, Biddy writes to Pip, saying that Joe will visit him in London. But, by this time Pip has become snobbish and he is anxious about Joe's appearance and behavior before his gentlemen friends. Of course, Joe senses this and tells Pip he will visit him no more; he tells Pip that he must come to the forge where he will always be welcome.
After his sister's death, Pip finally returns to the forge with much uneasiness and guilt. He displaces his guilt by being harsh with Biddy, telling her "I think you might have written to me about these sad matters." To this, Biddy perceptively and ironically replies, "Do you, Mr. Pip?....I should have written if I had thought that." As they converse, Biddy tells Pip about his sister's demise and asks pointedly if he will come to see Joe, really. Pip is offended and scolds Biddy. As he leaves, he has the boldness to tell Biddy that he is not angry with her, but "I am hurt." But, Biddy is right; Pip does not return to the forge for a long time.
Clearly, Biddy, in her simple and honest and humble manner, is a foil to Pip. She is without guile. Even when Pip returns and is accusatory, Biddy speaks calmly to him. As Pip finally returns home, the prodigal son who begs forgiveness, he asks her to receive him as well. The Pip is so bold as to propose marriage to her, but Biddy does not offer any reprisals. She simply lets Pip days later discover that she and Joe have married. Yet she remains ever the friend to Pip, encouraging him to marry. And, when she and Joe have a child, they name the boy Pip.