If you neighbours are Chinese, it could well be that they aren't aware of the level of noise the kids is making, daft I know.
Most of the Far East is, except in Japan where they are very aware of the noise they make, quite tolerant of noises, particularly from children.
My neighbours would regularly scream to each other from house to house at 6am and then around 6:45 the local head man would come on the village tannoy system and talk drivel for 25 minutes before playing crap adverts for local companies full blast.
My advice is to go knock on the door and ask them if they can possibly keep the noise of the screaming kid down.