I have 3 kids ages 9 mos to 6 years, and they loved this place. It was very well equipped for a family - toys outside and inside, stools near high sinks, plastic dishes for kids, etc. And the beds were very comfortable and bedrooms felt serene. We would definitely rent it again on another visit to LA!
One thing I would mention - the roads in Mt. Washington are very steep and narrow - not good for taking a walk or a run (in my opinion :)) if you want to do that from your front door.