Who is the solitary child in A Christmas Carol by Charles Dickens?

In A Christmas Carol, when Scrooge looks back at himself as a young child, the Ghost of the Past tells Scrooge, "The schoolroom is not quite deserted. A solitary child, neglected by his friends, is left there still...." Scrooge struggles to even look at the image of the young boy (himself) from his past as he is surrounded by feelings of insecurity. This part of his past becomes the foundation that he uses to build the figurative and literal wall (of money) around himself, convincing himself that like the little boy, he does not need anyone. He is a lonely little boy, with no one to love him. In this trip to the past, he is reminded of the solitary child he once was.