(early) morning dreams come true
The superstitious notion that dreams one has in the very early hours before one wakes up are fated to happen in real life. A: "You see! I told you that would happen—Morning dreams really do come true!" B: "Bah! That's just a coincidence!" My mother always believed that early morning dreams came true, so if she had a bad dream before waking up, she'd refuse to leave the house.
Morning dreams come true.
Prov. If you dream something in the morning, it will really happen. (According to a superstition.) As I was sleeping through the sound of my alarm clock this morning, I dreamed I was late to work. That morning dream definitely came true.