What are the nightmares of a second child?

John and I woke up startled in the middle of the night to hear Nora yelling from her crib. We sat up in bed to further observe what was going on with her. (No need to get out of bed since our apartment is so small that her crib, even in a different bedroom, is about six feet from our bed.) Nora forcefully yells, "No it's MINE! IT'S MINE! No! IT IS MINE!!" and rolls over and grunts and goes back to sleep. There's a little window into the true fears of a second child.