FamilySearch has been indexing their images for the Cook County Birth Reports (1878-1922) (Currently input through 1915)
Below is the Birth Report for an "Edward Cruvant" son of Ben Cruvant and Lillian White. Ben was my great grandmother's brother. Approximately 1903 Ben and his father Morris traveled to Chicago, perhaps exploring the possibility of moving the family there. Ben and Lillian were married in May of 1904. Edward was born two months later. A sister, Sarah, was born in July of 1905. East St. Louis City Directories indicate they'd moved back to St. Louis by 1907. By 1910 Lillian and her two kids had returned to Chicago, and Ben remained in St. Louis, remarrying in 1912. The existence of a first wife and children wasn't hid from his second family, but no one knew what had happened to them.
In the 1910 census Lillian's son was indexed as Clifford E.
What's really strange, is that on FamilySearch, he is indexed as "Clifford Paul." The name Clifford appears nowhere on the Report. Nowhere at all. The image clearly says, 'Edward.' Please feel free to look at the image below and verify this for me, but the name couldn't be clearer. If I didn't know about the 1910 census I would scratch my head and really question the eyesight of the poor indexer, or maybe think there was some database error where the given name from one certificate got indexed with the surname from another . Because of the 1910 census, I know the odds are good this wasn't a mistake. My assumption is that the indexer had another document in addition to the Birth Report. A document they haven't scanned in. I want to know what that document is, what other information I might expect to find on it, and where I can get a copy of it.
Update: Cynthia at ChicagoGenealogy not only tells me what the document was (a Certificate of Correction) she finds it on the Family History Library microfilm and scans it in for me. Thanks!
The FHL copy doesn't include the date of the correction, but the County Clerk at the time of the correction was the 'infamous' Michael J Flynn, who was County Clerk from 1934-1950, so the correction was at least 30 years afterwards.