I forgot to mention (a couple of weeks late..) that Ivy got over her illness. It lasted a couple of days of her being sad and unwell, but she quickly got back to her usual happy self (although her sleep cycle is now messed up). She still has a lingering wheeze, which means that she sometimes sounds like a cat purring when she breathes, and when she babbles it's like a growl. (The doctor says she is fine and that this is normal.)
Just look at that happy, cheeky little face. Sometimes I *squeee* out loud and have to squish (cuddle) her.