You had me stumped for a minute there with the "3 kittens in the house" statement. I mean after all, this IS PT where everyone keeps finding and adding. Anyhow, so pleased the younger is getting the older ones off their duffs!

I used the double sided sticky tape with good results. I also rub catnip on the scratching posts to make it MORE enticing, and squirt the vinegar and water mix on the furniture to make it LESS enticing. I did all that for about 5 weeks each time I had a cat who didn't "get it."
Good luck!