I didn't want to alarm you about the possibility of internal ones..it's probably very, very unlikely. I just thought I would mention what I had read in case you wanted to ask about it as a question at your appointment. Thanks for posting the picture. Judging from the size of it and what you said about it growing very slowly, I'm guessing they might just watch it for a while, but I could be wrong. By the way, he is so cute!
Keep us posted!