“At the top of the stairs, a once sad, low-ceilinged room (it’s only 4 feet) is now a sunny den, just the right height for the girls. Removing the dark railing in favor of white banisters helped flood the windowless space with natural light. “Kass’s daughters love to read, and this is a cool little retreat separate from their bedroom, where they can hang with friends,” Roche [formerly Hassen] explains. She followed suit in their parents’ mezzanine-like bedroom overlooking the Harry Potter space, swapping the visually heavy iron partition for a wall-to-wall glass panel instead.”