“And I keep as many secrets from you as I can.”
“Ouh, like what?”
“I’m not telling. That’s the point.”
“Ah, of course. But I must say that is a little rude, if you don’t mind me saying so.”

Sadly, luckily, however you want to view it, she and the others aren’t THAT good at keeping things a secret from him. They are pretty good though…

Oh, and for the past I’m kinda sure “changeling” is a catch-all term for shapeshifters until their original form is revealed.