All I remember about this book is that it was a mystery-type story centered around a group of kids (I think they're related). Story takes place in Florida/key west/key largo keeps coming to mind. They're staying at someone's house, maybe an older relative? The kids keep seeing these colored animals running through the house (i.e. a blue dog), one for each kid. I think they sleep on waterbeds. Other things that happen: someone gets pushed into a pool, they go mini golfing maybe? This is driving me nuts! Probably read it about 10 years ago.