DD has always been a chatty sort which was sweet but she has now developed a loud, V loud shriek that she uses when we are out and about. Most especially in quiet surroundings such as coffee shops and libraries. It really is piercing. now i have tried the ignoring it and chatting away to her when she stops it but - it doesnt seem to be working. is this usual for this age? is she just practising to become a member of a girl band in later years or should i be concerned??