Casey (and most definitely, Kacie) seem like a bit of a stretch as nicknames for Carissa. I can see a bit of a visual resemblance between Casey and Carissa, but other than that, not much else is similar. Katherine and Katie don't really sound alike either, and I realize that it's not imperative that nicknames sound like full names, but Carissa "Casey"/"Kacie" still strikes me as on the odd side.
This message was edited 9/13/2011, 7:52 AM