A safety device for an automobile such as a car or a van, the safety device being a window insert designed to fit within the standard frame of a window and be retained within the frame by the upper edge of the window fitting within a groove configured on the lower edge of the window insert. The window insert may include orifices to allow air inflow and/or outflow so as to provide a continuous flow of fresh air into the vehicle. The safety device may be used to retain a child or a pet, and can be formed from a plastic, plexiglass or polycarbonate material. Alternatively, the window insert may be formed from a high impact or bullet-proof material.