First of all what is the NAME of the movie so we can draw an idea of the context?
As for Reincarnation.....
It would seem that yes beings come back as infants.
I have read of 'Walk Ins' or 'Wanderers' but, that is a different story.
Most of us have reincarnated many, many times.
There are those that do not believe we incarnate at all.
I find it a 'waste of space' for us not to have repeated incarnations.
Reincarnating makes perfect sense to me.
I even had a Past Life Regression session recently and confirmed a few things about myself that I thought was true.
Here is a link that can help give you a basic idea at least....
Afterlife101:
http://www.afterlife101.com/Chapter5.html