Schatzie get's angry at the vaccum. She barks at it then goes and lies down until I am done.
Maybe with your little one in the room, start the vaccum for a few seconds, turn it off and give Gracie a treat then turn on the vaccum again. Then repeat it maybe two more times or so. Maybe after a few days of this Gracie will realize that the vaccum isn't so bad after all and will get used to it.
Just a thought and hope it works.
Good luck,