Thank you both for your replies
It hadn't occurred to me that we might actually be rewarding her for being in the room, so I'll definitely be taking that on board with more playtime and treats when she comes downstairs.
We feed her downstairs so that won't change, and I'm planning Phase One of making changes to be moving her litter tray onto the landing (which is a low-traffic area) so hopefully that won't be too upsetting for her.
My main concern really is that this room is the only place she'll sleep (usually on a sofabed we've got in there) - for some reason, even when we're out, she'll never settle on either of the sofas downstairs, the dining room chairs or any other surface. She also has a huge cat tree in the room, which she loves, so if I can find a similar spot for that somewhere that should help.
Anyway, like you said - where there's a will there's a way! I'm determined that Baby and Fur Baby will live in harmony!
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