It's possible she squeezed into it through a small hole that allows her to get in but not out. My parents used to have a cat that did that to the area underneath a bathroom sink, constantly getting stuck and forcing me to find a way to get it out.
If that's the case, all I can tell you is that you might need to ruin part of the couch to open up a hole.
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Not changing this sig until I decide to change this sig.
Started: July 6, 2005