[Drago]

To resolve excessive nail length, you can add a pile of smooth, sterilized, and rounded stones inside the enclosure. This will keep the nails trim and provide an extra climbing type toy for her so it's a two in one! As for the nibbling/biting, almost all hamsters will nibble if you put your finger near their mouth. It's just a response they have, like when you look at an object when it's placed in front of your face. To try and stop nibbling/biting, if recommend you have short sessions where you place your hand near her nose and when she sniffs, licks, or ignores your hand, reward her with a healthy treat. If she bites or nibbles, push her away (very gently) and do not reward her. As for your cats, I don't think it has anything to do with her behavior, but I would still try to prevent your cats from doing this as it can stress her out. If you have any other questions about Milly, ask away!