It would appear on the surface that two entries for the same person in an index would be at best a duplication and, at worst, a mistake.
In this situation, the reality is somewhere in between.
A search for Lillian Apgar in the "Cook County, Illinois, Birth Certificates Index, 1871-1922" resulted in two entries--both with dates of birth as 2 March 1910 and parents as William and Mary.
The "more about" screen for the first entry provided the following information.
The second one showed the following and contains more information. The names of the parents are the same except the maiden name of the mother is one word on the second entry.
The FHL film number from which the index entries were created is different.I searched for the film numbers on the FHL catalog to see what microfilmed records were used to create the index entries.
The first FHL film number indicated that the first index entry was made from abstracting the birth register.
The film number for the second indicates that the information for that entry was taken from the birth certificate as shown below.
Yes, the entries are for the same person. But they are not entries made from the exact same record. One entry is made from the birth certificates and the other is made from the birth register. The birth certificates are filed in a bound volume with one certificate per page. The birth register is a ledger that has one or more lines devoted to each birth.
If I had bothered to read the section on the "original data"
- "Illinois, Cook County Birth Certificates, 1878–1922." Index. FamilySearch, Salt Lake City, Utah, 2009. Illinois. Cook County Birth Certificates, 1878–1922. Illinois Department of Public Health. Division of Vital Records, Springfield.
- "Illinois. Cook County Birth Registers, 1871–1915." Index. FamilySearch, Salt Lake City, Utah. Illinois. Cook County Birth Registers, 1871–1915. Illinois Department of Public Health. Division of Vital Records, Springfield.
the potential reason for the duplicate entries might have been surmised. FamilySearch and Ancestry.com do get things tangled up upon occasion. This is not one of those times.
Lessons and reminders:
- Learn what you are actually searching.
- Be aware of multiple records. In this case the register does not contain as much detail as the certificate. And even a record that is less detailed may be easier to read than another one.
- Cite specifically. If I just list this as "Lillian Apgar birth information" in my sources--I can't tell whether I saw the record or the register. There's a reason why being specific in a citation is advised.