A pop up cover for a crib is provided for providing a safe, comfortable and isolated environment for a child in a crib. The pop-up cover may be made of breathable fabric panels having an integrated frame, for example a flexible frame, which can be folded (collapsed) on itself, for example when folded in specific ways if appropriate force is applied and which keeps the fabric in a taught, open position when unfolded (preventing the panels form falling inwards onto each other). The pop up cover can be lightweight and compact, quick and easy to set up, dark inside and breathable.