Hi Maxwell
These Easter kitties sadly make only their first breed together a special costume kitty :-)
Congrats with the Aby Lilac though so cute I love that fur!
It is possible though to breed kitties which make a costume kitty together first with other cats after which you partner them together to make their special kitty.
As long as they never had a special kitten before because they can only have this one time :-)
I hope this helped to clear that up.
I'm quite curious what fur your Aby Lilac hides!