I too have worn glasses since I was about 2. I am also long sighted. Both of my eyes turned in and they had to do an op. The left eye was fixed but my right eye still turns in when I am not wearing my specs.
It is good they have gotten to it so early. Like lime slice said, by the time they are 10 the eyes are kind of "set"
They grind down the specs now so you cannot even tell what strength they are.
Its hard not to fret but glasses are so common in school these days.
And it is good they are working on fixing his sight now rather than later.