My 6 year old daughter has been coughing up these for about 1 year. The first time she did this, i was very concerned thinking she had a tumor, so I saved it and took her and it to the doctor. He informed me that it was the lining of her tonsils and not be be concerned. So about 8 months later, she starts again and I have told her to let me see it everytime she coughs them up. She came home today from school with it in a napkin and it was huge and smells awful. So I did a search and found this site and was shocked at how many people have this. She always tells me that there is something stuck in her throat.
I guess I will have to call the doctor and see what they suggest.
I do notice that her breath smells bad from time to time even after she brushes her teeth. I just noticed it this week and today she coughs them up.