Is it normal my son has the same indescribable night terrors as i?

My son is now 14yrs, a strapping lad. I happened to ask him, after not seeing him for some time, if he still had the same night terrors that were so frightening for me as a father to bring in out of them. I asked him to describe them. He tried to explain, but could put a name, colour or shape to it. He says sometimes the 'thing' still comes but stays on the outside not allowing him to analyse it. The strange about it is that I've had the exact indescribable dream all my life. I used to tell him to fight it when he was trapped and to take control. Over time it must have worked, that plus age. The most we jointly can define it is as a pure evil blob of nothingness. It is always there lurking, but does not come within reach to be defeated.