If you are a size 12 in NZ you are small, 8 to 10 petitie infact you would be pushed to find a size 6, but some stores do stock those sizes .
14 is average and 16 and up above average.

There are plenty lovely clothes here in size 12 and 14 to choose from.

yes a lot to cater for the younger ones, but we do have some stores that you can get shirts and pants as you describe Laura's Babies.