Do babies dream? Probably - just not the way we do

Newborns spend a huge share of their sleep in the active phase, the one that in adults carries dreams. That's when the baby twitches, grimaces, smiles, moves their lips. Parents read it as nightmares; it's simply how that phase looks.

What a baby could be dreaming about, nobody knows - there aren't many images or words in there yet.

Real story-shaped dreams, and the first nightmares, arrive closer to two or three years, when imagination does.