鄭太
it's true that it's very common for baby to have favourite position in sleeping. exp for bb who likes to sleep a lot, they tend to sleep on one side and result in a flat head on that side. in most cases, changing positions and rubbing the head will help solve the problem. however, in more severe cases that the flattened of the head shape will eventually result in strange facial structure, that means u can tell by just looking at the face. in this scenerio, the dr will prescribe special treatment. i know this because my friends' baby went through it. so if the dr did advise about the shape of the head, you may be should take it a bit more seriously to advoid futher treatment.
the treament is actually require the baby to wear a helmet 23 hours a day for several months. it doesn't really bothers the baby but it's really a hassel.