I am convinced that there is no sexual aspect of this desire and there is nothing wrong when the moral norms of society and the medical office policy allow it.
You and many other mothers may be convinced - and when has a mother ever been wrong in her feelings? ... but you can clearly read from the many instances recounted here, and with a bit of (that famed) female empathy and simple observation, you should be able to see it before you in the doctor's office, that not many boys really like having parents and especially mothers present at such moments. What's so difficult about this little bit of empathy?
I know you changed diapers and all that, but that doesn't mean that those motherly privileges last into puberty. It shouldn't be that difficult to understand. But it is in many cases helping to form the basis for a very healthy medfet attraction later in life. So that's something on the plus side ... ha ha