That's why I put my tree up in my home office where I can close the door and keep my boys away from it.
2008 was the first year I put a tree up since I got the cats. I initially just put the lights on and let Chessie and Casey in to see how they would react to it. Chessie went up to it and just stared at it in awe. Casey went right up under it and began rubbing against it, causing the tree to sway. So while the tree is up, no cats in my room.
However, Smokey (aka "The Daredevil") thinks he has to be in here and tries to run past me to get in. One time last year, he was successful, and I was able to grab his rear half just as he started up inside the fully decorated tree.
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