The Ghost shows Scrooge things he had forgotten and brings him a vision of his dying sister Fan who begs that Scrooge cares for he son (Fred). Scrooge is unaware of the last words of his sisyter and is mortified taht he did not keep this wish, indeed he is beside himself with grief as he has cut Fred off without a penny form the day of his sisters death giving birth to Fred. He is also shown when he changed and started to harden. he losses his beloved Belle because he is not more focused on money.
The ghost of Christmas Past showed Scrooge visions of his past, allowing him to reflect on the choices he made and how they have shaped his present life. Through these experiences, Scrooge was able to gain insight and understanding about his past behavior.