Sillabub

Hi I am 9 and just saw Cats this week. The show had Sillabub in a blue cat costume and they said she was the blue cat. Why?

Also why is Rumpus Cat in the DVD and not in the show. We had a really funny Griddlebone and nit the scary Siameses this time. Ithink it is because the stage was so small. Thet only had 17 cats all together on the stage.

Thank you.