Well there are some similiarities of Kuman Thong and other "Ghost" in other beliefs. For example,The Kuman Thong is kinda similar to a Malay Child Spirit called "Toyol" or "Anak Kerak".
Keeping the fosilised foetus will result it getting good fortune but not being able to satisfy the Anak Kerak will bring you big trouble.Anak is a malay word for child and Kerak is a malay word for crumps( Think Bread crumps).
Anak Kerak is believe to have come from a dead foetus which was killed on purpose while still in the womb.
The best foetus to be made into an Anak Kerak are believed to have come from the 1st child from the parents who are also the 1st child.
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