Please don't declaw if you can help it. And check on certain vets and get client reviews. Some vets are very sloppy with it. Trimming nails is much better. So are loads of cat trees. If you can afford the surgery, you can afford several cat trees. Mine love the kitty-only furniture. Cat's need to scratch; it is part of their nature. I sprinkle their trees with kitty nip, too. And don't stick the trees in a corner at first.

Is there a reason only one is being declawed?

Mine get rabies because it is required. The younger ones do get some vaccines for a few years. You also never know when your neighbor's dog might have contact with another cat that is sick.

Please consider what we have said here.