Can empathy be taught to kids who don't have a natural inclination towards it?

Long story short, I have a 3 boys ages 9, 8, and 7. The 7 year old doesn't outwardly appear to have the same natural empathy as his brothers. He's a good kid and the least aggressive of the 3 so I am not worried about behavior. He is my quiet and introspective kid so he could have more empathy than he lets on but outwardly it doesn't seem as strong as either of his brothers at the same age. We always kind of figured it would develop but now I am wondering if we need to take extra measures after his reaction to an event involving one of his brothers yesterday. via /r/Parenting http://bit.ly/2WjRUr4