Part of Scrooge's redemption is to see his effect his treatment has on others, and see how he had been treated. His disregard to the destitute was summed up in the line "If they would rather die, they had better do it, and decrease the surplus population." When he travels with the Ghost of Christmas Present to the Cratchit's, Dickens has Scrooge say " Spirit,' said Scrooge, with an interest he never had before, ' tell me if Tiny Tim will live. ' " Scrooge is ashamed when he hears his statement repeated back. It's evident that after reviewing his own life as a child in Christmases past, and now witnessing Bob with his family, he's begun his transition and has begun to have some sympathy for Tiny Tim. After his redemption, Dickens states that Scrooge became "a second father" to Tiny Tim, because he's learned it was in his own best interest to help where he was able.
In the third stave of A Christmas Carol, the Ghost of Christmas Present takes Scrooge to the home of the Cratchit family. There, Scrooge sees first-hand the plight of Tiny Tim who, despite suffering a serious medical condition, is a kind and compassionate young boy. Seeing Tim behave in such a way has an impact on Scrooge:
"Spirit,'' said Scrooge, with an interest he had never felt before, "tell me if Tiny Tim will live."
This interest is further developed in the next stave when Scrooge sees a glimpse of the future in which Tiny Tim does not survive. Scrooge realises that if someone like Tim, who is so disadvantaged and deprived, can care for those around him, then everyone ought to behave in the same way. For Scrooge, this is a turning point in his life: he realizes that if Tiny Tim really dies, all that is good in the world will die with him. This inspires Scrooge to care about Tim's fate and, in the closing lines of stave five, we learn that Scrooge becomes a "second father" to Tim.