Hi there Diane!
Congrats on your twins! Twins are a rare occurrence and can be either Identical (both exactly the same) or Non-Identical (both different, either traits or sex).
In your case, one of your twins has a Surprise Birth Costume on! Between April 1st - 10th everyone breeding cats would get 1 in a surprise costume to celebrate April Fools day and Easter! The costume is just a fun mixed up design over your cats actual traits. You can view the cats actual traits by clicking on the cat > Online Help > Go to the page it gives and click to view the Pedigree Tree for the Cat. That will take you to the cats Online Pedigree page where it will show you the cats parents and all the cats info including their actual traits!
I hope this clarifies things a bit. If you have any further or other questions, feel free to reach out to me in world or through our support system
Congrats again and welcome to the KittyCatS family!
-FoxieCat