The souls of people don't necessarily immediately leave this plane, especially if they have died unexpected deaths. The best way to handle the situation of an unexpected death of a child is to have a short memorial service for the miscarried child and "give them over" to Jesus. The best reason to give is it is psychologically for the parents.

The first time I experienced this phenomenon of wandering souls was on a highway where my mother had suddenly died the day before of a violent car accident. I went to look at the skid marks to recreate the accident in my mind. I felt this "presence". It felt like my mother. It was totally confused and disoriented. I pointed to Jesus in heaven and said, "Mom, go to Jesus." I felt comprehension dawning on the presence and it moved upward, picking up speed as it went, to Jesus. I never saw anything physically, just spiritually. THAT'S the one that gave Hebrews 9:27 a different meaning to me.

I led an ecumenical group for a while. One of the members died rather quickly of cancer. A week later, while I was typing away on my computer, It felt like Gigi was looking over my shoulder. I said, "Hi, Gigi" to an otherwise empty room. After a couple of minutes, the sense went away.

A woman came to our center weekly over two months. She and her neighborhood had numerous problems. We cleaned up her neighborhood from that prayer room, but her problems weren't getting resolved by our combination of prayer, deliverance, inner healing and breaking generational curses. One week she mentioned she had sores on her legs exactly where her late husband had sores. When asked, she said she had been there when her husband had died. That's about the time her problems started. 
   Having tried everything else we knew, I launched out on an experiment. "What was your husband's name?" "George." "Well, George it is time you left." Nothing happened. "George, you are no longer married to Ann. When you died, the marriage was ended......" At that moment something came up out of Ann, brushed against me and headed up out of the room. (Demons never do that.) Ann raised her hands, shouting "Glory!" The other two prayer ministers in the room shouted, "Whoa!" Ann was healed.

I was led to clean up a battle field in Georgia to bring healing to the region. I pointed my finger to where Jesus is, on the right hand of the throne of The Father in heaven and then called out, "Come to Jesus." The four people I was with suddenly dropped prostrate or on their knees. What they saw was white figures racing towards me and forming a tornado going up in the direction I was pointing. I didn't see anything; I felt a slight brushing sensation.  This went on for over five minutes. Finally it tapered off.  The region spiritually lightened up.

There's a book called Healing the Haunted by an Anglican priest, Dr. Kenneth McAll that explains his ministry to lost souls. It's one of the most bizarre books I have ever read! But my personal experiences are congruent with it. However, as a priest, he naturally promotes the service of Eucharist to resolve this sort of thing. I'm a Christian layman; I don't.