To daydream, one should have a developed brain with collection of scenes in mind or expectations connected either with past, present or future. Other main cause of daydreaming is laziness. When you are lazy, your mind will start running everywhere without any aim. That is also daydreaming.

Those will not happen with small babies but instead they dream asleep.

We have noticed that newly born babies are smiling asleep. They are definitely dreaming.

What?

Who knows exactly?

I can still remember my grand mother told me in my childhood, that the babies asleep are smiling with beautiful fairies of snow white, who had come with lot of toys to see and play with them.But can they identify fairies, colours and toys?

I do not Know?

Psychologists will definitely furnish an interesting explanation for this. We have to accept it because they are the Specialists in this field.