At a minimum, you can call and add it to your reservation that you would like to celebrate at dinner. I would remind/double check with your servers, as well. But they will bring a cake and sing. I'm sure there are other things you can do but this is a start.
The cake and singing at dinner is standard. You can buy "room decorations" for $30. I do my own decorating and do a small family gift in addition to the dining room celebration.
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