Some parents did not name their children immediately, so you can't assume that the child was stillborn. I have one relative listed on the federal census as "No Name" because the parents had not yet named him, even though he was six weeks old at the time of the census! I can't imagine why it took so long. you may want to search the town's death records and burial records in the local cemeteries to see if there's a record. If not, look for a female child ~age 12 on the 1900 census record with that family.