As first seen on blog "Organized Mess" here: Cold Weather Essentials: Layer Under a Dress
She is wearing tights similar here: Black 200 Denier Opaque Tights
Black fleecy opaque tights 200 denier. Snuggle into extremely soft and cosy 200 denier fleecy opaque tights. With thermal properties, the tights are smooth on the outside and fleecy on the inside to keep you nice and warm