My wife and two small children (age 2 and 4) spent a month at Villa Windsong in August. I wanted to get away for a month to work on writing a book, and needed a place where I could find privacy as well as a place that my family would enjoy as well. Villa Windsong absolutely hit the mark on all counts. It's extremely kid-friendly, having its own beachfront, treehouse, swings, and lots of room for running around. It has a wonderfully equipped TV room/office with AC and wi-fi internet. My wife fell in love with the kitchen, and we all fell in love with the infinity pool. As others have said, the pictures don't do it justice. If you've stayed at other private villas, you'll definitely appreciate the experience here.
One note relative to your potential expectation is that the beach itself isn't swimmable for anyone but the strongest swimmers as there is a rock shelf that runs the length of the shore. There are sand and waves for building sand castles and hunting for shells, but you have to keep a very close eye on the kids. It looks beautiful though, and we loved sitting on the chairs by the pool just staring at the view while the kids played in the pool.
Our only regret is that we didn't invite more people to come visit us while we were there!