When Aaron West was born, he had a Chicago Cubs nursery waiting for him at home. As his dad, Chris, put it, it's a baseball family.Though Aaron was born without a fully formed left hand, that did not stop him from hitting the ball field like his dad and his older siblings."As soon as he started walking, we couldn't keep him off the field," said Chris West. "I was on a softball team, and when he was 2, he would grab a glove and go out and try to take my spot on the field."Now, at 6 years old, Aaron …