It's been a month now, so he should be at least 2 cm taller by now, perhaps a whole inch. By January, he should be closing in at 2 inches. At this point, he will very likely start developing the well-known "Duck Ass". Because his thigh muscles are stretched by a good 2 inches, they are extremely tense, and won't allow him to stand straight. His torso will be leaning forward with his ass sticking out like a duck, hence the name. His legs will start to get skinny too, and he won't be able to walk for very long on his crutches before he has to sit down to rest. Sleeping properly (or at all) will be extremely hard, and he will probably have lost about 30 lbs. With regular physiotherapy, he may reduce these problems, but he won't be in any real pain. However, some people get nerve pains in the calves due to the stretching of the nerves, but there are also special meds for that.
Reaching 3 inches is difficult, but most people who really want it badly will get there through persistence and determination. After 3 inches, some people re-evaluate their original goal of 4 inches because they either think that their legs are getting too long, or they just don't want to endure it any longer (or both). Many will choose to stop at 3 inches, some will go to 3.5 inches, and just a handful will go all the way to 4 inches when further clicking is no longer possible. So there's Cute-Bald's life for the next three months while enjoy our wonderful lives.