A close friend of my parents hangs out with our family a lot. He is sort of like an older brother to me. One day, we were talking, and he started talking about how "we both have ADHD". The problem is, I have never been diagnosed with ADHD. He has, so I guess he thinks that I have it as well. Anyway, he sometimes brings it up when I have friends over and it gets awkward because they think that I have been keeping a secret from them. Is there anyway that I can get him to stop without hurting his feelings?