And then Tracy paused and let out an almost imperceptible gasp of air. I could see why, at once. She wasn't looking at the stocking, or at mom's leg. She was looking past it, to the uncovered spot between mom's legs. Mom had parted her legs to let Tracy pull the stocking on, and now Tracy could see that mom wore no panties. She could see her pussy. Mom looked steadily at Tracy's face, without so much as changing her expression. Tracy raised her eyes from under mom's skirt to mom's eyes, and then she looked up at me. I wanted to laugh, but I kept an even expression and...