Until last year, I was always a sleeveless cotton Nightie girl, whatever the weather, but decided I needed something warmer for my old bones. Picked up some oversized t shirt shaped nighties that don't cling from Asda and Sainsburys and some very loose pyjama bottoms. More like yoga pants. I think they're all Viscose with 5% elastane. The tops all have a deep scoop neck as I can't abide anything muffling me up. When it got really cold I put a cotton camisole under the top. Also bought some slightly heavier weight nighties from Taking Shape. They're made from bamboo and feel heavy until you put them on and they hang beautifully, no clinging. I actually bought a long sleeved one which I am planning to wear with thick tights as a dress.