My son Jonas had his tonsils taken out about 5 years ago. Initially, his sleep quality improved dramatically, and his snoring disappeared. These days, I hear him snore occasionally, and he does seem tired, but only when he doesn't sleep long enough. Does this mean that his tonsils have grown back?
The short answer is no. When you take out your tonsils, just like taking out your appendix, it can't grow back. If you undergo an appendectomy and still have abdominal pain, than that means that there's another problem that's causing the problem. Similarly, if your snoring comes back after tonsillectomy or any other procedure that opens up the airway, persistent or recurrent symptoms means that, there was something else that was not addressed.
If your child has persistent or recurrent snoring after undergoing tonsillectomy, it usually means that there are other areas in the upper airway that is causing narrowing of the breathing passageways, from the tip of your nose to the space behind your tongue.
In general, the reason why your tonsils grow to large sizes during ages 3-6 is due to increased activity of the immune system and enlargement of lymphoid tissues. Since your tonsils are lymphoid tissues, they will get bigger, especially is there's an additional source of inflammation. Children who are prone to breathing pauses (due to narrowed jaws), along with eating habits that promote inflammation (such as eating late), have an additional source of inflammation: stomach juices.
With every pause in breathing, a vacuum effect is created and whatever juices that are lingering in your stomach is suctioned up into your throat. These juices include acid, bile, digestive enzymes, and bacteria. It irritates your tonsillar tissues, causing them to swell, which can narrow the throat even more. Furthermore, these juices can even reach the ears, sinuses and the lungs, causing further inflammation and swelling.
This is why despite an overall 66% success rate with tonsillectomies, there's a high rate of relapse. Some physicians estimate that over time, over 50% will relapse with increased snoring and progression of sleep-breathing problems.
Taking out your your tonsils, although it can be helpful initially for some, doesn't really fully address your entire upper airway. By definition, narrowing can occur from the tip of your nose to your tongue base area. If your tongue if a source of obstruction during sleep, then you'll prefer to sleep on your side or stomach. So if you suspect that your tonsils have grown back, look at these other areas first, before thinking about your tonsils.