Child's Play...Should I have concerns?

I was quite irritated by the twins curiosity in all the rooms but their own, so I had them come and play next to me in the living room. Sabrina was the doctor and had the doctor kit out. Olivia was not sure what to do, so I suggested that she be the mom, taking her sick child in to the doctor. Olivia climbed up on couch and sat there looking at the baby doll.

I suggested that she tell Dr. Sabrina, what was wrong with her baby. She looks up at me and looks over at Dr. Sabrina ands calmly almost morbidly spurts out, "The baby's dead."

My friend and I look at each other and burst out laughing.....it was so unexpected from such a little girl. Now the morning after, I wonder if I should have any concerns...........