The website for the spa is the following:
http://www.relaxedyet.com/
I don't think you can find the link at the website, I ended up calling last year to get the web address.
I did this last year with my children, I put them in Grand Adventures in Cooking while I had a massage. It worked out great.
I would make my spa reservations ASAP, as I remember having some difficulty getting the time I wanted. I initially couldn't get the desired time, but I called back a few weeks later and was able to get in.
Good Luck and enjoy!