Hope this is of help:
1) Children have 20 deciduous (baby) teeth in total and these will all be lost between the ages of approximately 6-12 years old
2) All of these 20 teeth will be replaced by permanent successors.
3) In addition, three permanent molars will grow in each corner of the mouth, to give a full adult complement of 32 teeth.
4) These permanant molars erupt at approximately 6,12 and 18-25 years, with the last one being the 'wisdom' tooth. This is assuming that no teeth are congenitally absent
As your daughter is 6 years old and has lost 5 of her deciduous teeth already, she is quite well advanced in terms of dental development for her age. It is thus likely that she has grown one or more of her first permanent molars behind the deciduous teeth, and it is this tooth that needs to be restored. It is true that when she is older the restoration could be changed to a 'tooth coloured' restoration.