Overly shy and unparticipating student...?

I am not an expert on kids by any means but my younger brother who is now 12, sounded just like the child you are explaining when he was 3-7. He was so bad that he would cry if anyone even looked at him. He grew out of it BIG TIME now he's going up to strangers and making jokes and is probably ones of the most outspoken kids I have ever known. Hopefully this is something she will grow out of as well. The best of luck!