Yep! The dawn dish soap definitely works but make sure you use a good conditioner and let it set for 3 or 4 minutes to really condition their coat and skin because the dawn tends to dry their coat and skin up. Also, be sure and keep it out of their little eyes because it will burn them...its not tearless.
Also...try Bio Guard shampoo. Its for puppies, kittens, dogs, cats, and even safe for us humans to use. It is a great flea shampoo that works WITH your monthly flea protection like frontline or biospot or whatever you might use. and It wont wash it off!
I love the shampoo!
Goodluck gettin rid of those pests!