This is a nice summer nightshirt made of soft (but very thin) knitted fabric.  I tried a size Large/Petite, which is what I normally wear.  It fit well but it seems shorter than it shows on the model.  I don't think I'd walk around in this one without wearing pajama bottoms.

I washed and dried it and it got even a bit shorter, though it still did fit.  I think I'd have felt happier with the usual length, not petite.