One of the easiest ways to get familiar with the silhouette of a period is to consult historic examples.  The more examples the better.  This day and age, the most accessible means of finding such examples is of course Google!  Many muesums of historic costume have their exhibits right online, saving you the trouble of buying a plane ticket.

Among a Google garnered images, for 1850′s girls dress, was this daguerreotype.

Now this child is considerbly younger than Kirsten, but you can see the style elements typical of an 1850′s day dress for a young girl.  High closed neckline, sleeves wide at the shoulders, narrowing to the waist, a full skirt and a O bodice.  The skirt is a toddler length, appropriate to the subjects age, with two growth tucks.

The bias cut on the sleeves is really appealing with the print and such a garish print might not have been your first choice for Kirsten while browsing the bolts.  But, if you want to bring more authenticity to your finished garments, make the bold choice.  To pick a stripe in the right scale, pull the Googled image into whatever image editing software you use and resize the image until the girls face is the same size as Kirsten’s.  Then cut a section of the picture out with the crop too (the picture could be too big to print in whole at this point), print and bring it with you to hold up against fabric.