Your LCD screen may be broken because the display is not working properly. Did your daughter drop the tablet on the floor? In that case, the LCD screen may have cracked and is the reason why the screen keeps turning white. If the cause is the LCD screen, you can replace it and see if the display works properly after replacement. If the display still does not work, then the tablet may be broken.

Have you tried charging the battery? If you plug in the tablet but the battery won't charge, the battery adapter may be broken. If so, try using a different battery adapter and see if that works. If you have exhausted these options and the tablet still does not turn on, then the problem may be with the tablet itself. In that case, you could try replacing the battery in the tablet because it may have run out of juice.

Have you checked your settings? Make sure your sound is not on mute. If the problem still persists, try plugging in headphones to see if the audio works with headphones. If the audio works with headphones, there may be something wrong with your speaker, and you may need to replace it to get the audio to work.

Try plugging in the power adapter, and leave your tablet to charge for a while. If it still does not power on, the power adapter may be the problem. Try using a different charger and see if the problem persists. If your tablet still will not turn on, the battery may be broken, and should be replaced. In that case, check out the replacement guide for the battery.