Now I don't think they are the same girl ! Twins maybe, or perhaps the girl on the right is a year or two younger than the other. Girl on the left seems to have a slightly broader and flatter face; girl on right has a straighter fringe ... but differences are very slight.
I'd say they're twins, or sisters only a year apart in age, who like to dress alike !
Thanks for putting them side by side (and if you click on the pictures they come up bigger !)