Hoover attachment

Mitzi knows the Hoover, she even asks for it. I have an attachment about 15 inches long which is designed for tiny spaces. I don't think I have ever used it in her sight before but I hadn't thought about that.  As I took the Hoover into the room and was using the attachment behind a bookcase she was perfectly fine and had even said: "the Hoover" but when I picked up the hose and attachment to take everything out of the room I got the loud Grey growl. 

Jane