Suggest Treatment For Night Terrors And Short Temper In Child

My 3 year old grandson is showing having behavior problems at daycare. The signs are: not following instructions , when put in time out and not staying there, hitting other kids. He is sensitive to hot and cold and loud noises, and startles easy. He has been having night terrors, and cries out in his sleep. He also drinks a lot of liquids. He only drinks milk, water, and orange juice.