What is Beneatha’s motivation to become a doctor? Act 3

In Act III, we learn that Beneatha decided to become a doctor when a little boy named Rufus fell off his sled and was severely injured while they were sledding. When Rufus was put into the ambulance, Beneatha thought his condition was beyond hope. When she later saw him and noticed his injury had only left him with a small line down his face, she became fascinated by the way a doctor can see a problem and fix it. She wanted to be able to do the same.