We have a cat who has worked out how to escape through our cat flap even when it is locked. She figured out how to hook up the door when it was set to allow cats in, but not out again. Now she has worked out how to batter her way out when it is locked in both directions. We now put stuff in front of it at night but she still sometimes gets out. When we went away our cat sitter ended up putting three wooden tables in front cos one didn't work!
Anyone had similar? Any solutions?