Thanks mnmom23 for your input. Given your questions, I thought I would add add a little more to the picture. First, the audiologist felt that the issue was with those little bones behind the ear drum. She had checked for fluid and there was no fluid - of course this does not mean there was not fluid there in the past! Also, she kept asking me for genetics about the family and stating that it could be a birth defect in the shape of those bones on the one side. His dad has loss in one ear as well but he thinks it developed as a young adult as he worked in the music industry. The audiologist felt my DS's main issue would be if he is in a noisy classroom and the teacher is not a loud speaker. If it is genetic I'm not sure why speech would have developed normally except to say that perhaps I speak quite loudly and things were easier for him on a one-to-one basis (given he was my first child and my second is almost 4 years younger)
Thanks,
Tiz