Holy fuck, i had to come here as soon as I heard this.
This is an audiobook written in 1912 about the Rosicrucian order. At the 55:00 mark (5:5?) the writer talks about how a Rosicrucian should witness a child die, so they can also witness reincarnation almost immediately.
Their logic is that an adult won't reincarnate for centuries, that their soul will linger in the invisible world for a lot longer – while a child's soul will be instantly thrown back into a body and you can actually witness this.
This gave me the creeps. How do you seek out to watch a child die, exactly???