Good luck.
Anyway, to answer the question "Why can't adult hospitals be like this?", the answer is money.
Kids' hospitals get a truck load of charitable donations, to the point that some of them actually have difficulty spending it all. That has certainly been the case where I've worked.
I once had some ideas for some educational projects for the kids' hospital where I was working a while ago - e.g. website with child friendly info, parent-friendly info, educational games, blah. A few friends and I were willing to donate some time and web-building experience in doing it. It turns out that via a series of dontations, they'd just employed one of the biggest graphic design/web design houses to do just that with a series of commissioned cartoons, DVDs, etc. - I've no idea how much that must have cost, but I could see it going way over $100k.