cat mouse spider

I dreamt I was at a picnic of sorts at a wealthy home. I saw a cat playing outside and I realized it was chasing a mouse. I didn't want it to get it because it was cute. Then there was a spider running around to complicate things. It looked like a huge daddy long legs. I wanted the cat to see the spider so it would leave the mouse alone. The spider seemed to go this way and that just out of the vision of the cat. Then finally it ran up on the cat's forehead and that cat noticed it and the mouse was safe.