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I can't speak for the quality of those tools, but I'd be wary of buying them without letting her try them out first. You can't really be sure that a tool will fit into an animator's work flow until they try it out. But it might be worth showing her and asking her if she'd like it.
If she does any traditional drawn animation, then a lighting desk is great. They're big and not cheap, though.
If she works on the couch instead of at a desk, a lap desk is great. I know someone who has this lap desk and swears by it.
If she doesn't have The Animator's Survival Kit by Richard Williams then she absolutely needs that. No animator should go without it.
I work from home 3 days a week. Over the last few years I've moved away from a desktop and now use my laptop full time. In the last year I've got back down to not using an additional monitor but that is more so I can pickup and move whenever I want.
I sit on the couch or my comfy office chair (with ottoman) most of the time. I eventually got a lapdesk and loved it so much that I bought a second one to keep at the office for when I'm there.
I think the real trick is to constantly look at what isn't working and to make adjustments instead of trying to set it all up in the beginning.
I also have an Ikea Laptop stand that is really nice for smaller spaces.