Thanks to BOF and JMoff for your replies. They were very helpful as I mover forward in this job.
If the infielder had either charged the ball properly or gotten it out of his glove right away, the hitter would have been out. I did not want to be seen as favoring my son over another player.
I found out that I was taken off the hook for the call when the head coach reversed the hit I put in the book and gave the second baseman an error, as JMoff suggested. My son was not charged with the earned run.