The Song-dynasty forensics classic Witness to a Prosecution recorded a method for unraveling such mysteries: dripping the blood of children onto the skeletal remains for their parents, and using the ability of the blood to penetrate the bones as proof of a filial relationship.
為了解開疑雲，宋代法醫名著《洗冤錄》中記載「滴血認親」的方法──將子女的血液滴在父母的屍骨上，以「血液能否滲入骨中」作為親子判定的標準。