From the Seller:
This little girl's summer dress is beautifully hand worked in a fabric typical of the period. It has a cream background with a tiny design in dark pink. The dress has the usual wide neckline, little trimmed cap sleeves, a drawstring at the waist and neck. All the drawstrings are present, which is quite unusual. The bodice is beautifully made with box pleats from waist to neckline. The skirt is very full, and draws up very prettily.
The condition is excellent, with just one timy mark on the back skirt. Otherwise crisp and fresh.
Measurements: Length 28". Across shoulders including sleeves 14" (the little sleeves are 3")
This could easily be either a little boy's or a little girl's dress. There really isn't anything to indicate gender. I believe this is from the 1840's based on similar necklines and bodice treatments existing in adult clothing at that time period. The seller indicates they believe it to be from between 1825-1830 in the auction's title. Below is a photo of a child wearing a very similar dress.