>>2931723
Guessing it's just a pop in frame with tension springs on either the sides or top bottom?
Replace the springs first, but that's probably not going to stop a cat. These are retainers for a storm door but might work for your application.
The screen will become the weak point then though, so make sure you know how to replace a screen, because you will probably have to after the cat goes through it.
>a screen spline roller tool and a roll of spare screen would be good yo pick up ahead of time