Young Edwardians were the first to regularily adopt less formal clothing and wear them in studio photographs.
This is no different from today when sports trainers and clothing are worn as casual day wear.
For women the late Victorian pinched waist had given way to the S shape.
This is a young woman's casual winter clothing.
She has a heavy Jersey intended probably for the hockey field and is dressed for warmth in an era with no central heating.
She appears bottom heavy which is part of the style. Beneath her heavy winter skirt she will have a heavy flannelette
petticoat or two and amply cut warm underwear. She is probably not wearing a corset but still adopts the fashionable S profile of the day.
Usually a Jersey will have a two button fastening at the throat but often a woman's Edwardian hairstyle could not pass undamaged through the neck openings without involving more buttons.
The problem could be resolved by simply wearing a Sports Cardigan which for that reason alone was more popular with women than the Sports Jersey.