Here is a Washington State link you may find helpful. It also gives a link to click on to report "cougar or bear" problems in your area. I would ask them if the pepper spray would work on a cougar, I know you can buy it for bears. Please just be careful, I would definitely stay close to your house. Cougars have been know to stalk people, I've heard stories of hunters being stalked. My son once came across one while hunting although it ran off when he stood up and it knew he saw it. If one is hungry enough you never know what it will do. My prayers of safety are with you and your family.
http://wdfw.wa.gov/wlm/game/cougar/dosdonts.htm