The Petite size is a smaller version of some of our classic shapes designed for a person who is smaller in body size as well as height. For example, our Short Sleep Shirt is often available in One Size and Petite. The Petite version is best suited as a nightshirt to someone with a smaller frame and who is less than 5’4″. However, many of our “One Size” customers wear the Petite nightshirt as a shirt. Its smaller body and shorter length make it ideal to be worn as a day shirt though it would likely be too short to wear as a nightshirt without bottoms. We recommend choosing the Petite size for sleepwear if you normally wear smaller than a US size 4 and are not taller than 5’4″.