Hi
If your cat is no starter cat, those are not transfer excluded holliday custome KittyCatS.
You can either set it for sale for 0 Linden for this person or you drop it in their inventory.
The last option is, with live cats, a little tricky because if the person is not online for example the cat will not have access to it's food and gets hungry and if it takes too long (3 days) it gets sick.
So an inventory drop I would only do if the person knows a cat is to be received.
I hope this helped :-)