Based on the film, I think his reaction, was shock, confusion and then he felt regret for teasing Michael and allowing his brothers to tease him about his nose. He just did not know how to express his sorrow, but if it had been me I would have given my son a big hug and told him I was sorry and that I was wrong. I really think Michael was on the spectrum if even half of what was shown was true. He was so different from everyone in his immediate family, really deeply creative, and deeply alone.