Size will be totally dependent upon the individual's measurements and teenagers come in all sizes. There is no size designation for 15-year-olds.
A 7 year old boy might wear a size 1 shoe, or he might wear a size 13. Some 7 year old boys with very large feet might even wear a size 2 or 3 shoe.
The average clothing size for a 10-year-old girl is typically around size 8-10. However, children's clothing sizes can vary widely based on brands and individual body types. It is best to refer to specific size charts or take measurements for the most accurate fit.
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depends on how "big" the four year old is
The different places you go, the sizes change. For instance a five year old might have to get a size 7 in order to fit because of the store's sizing. For a 4 year old, generally it is toddler size 4,5, and some cases 6. Make sure it fits well! :)
small most likely
nothing, let them wear what they want.
24 months
It's not an age. It is just a size small. Like if you're 6 years old you might wear a size small or if you're 11years old it's possible to wear size small. It just depends on the size of your body.
size 12 or 14
It depends how large that 5 year old is. Kinda like asking what size shoe do men wear ?
usually about size 3 or 4.