"Oh, he doesn't care that much with what I do or who I marry or interact with, as long as I don't get in his way, but he does like to keep an eye on his progeny."

Okay, so that was a term that was more frequently used when talking about individuals a vampire had sired (which was what he was actually talking about here), but Thomas figured it was still somewhat ambiguous. Sort of. Since he didn't know what sorts Caroline had invited, he didn't know if everyone here would know she was a vampire, so he figured it was best to not directly say anything that was too obvious.