Before joining Find-A-Grave, I was not familiar with the term “cenotaph” until I read its definition. Not exactly the best definition – https://www.dictionary.com/browse/cenotaph
a sepulchral monument erected in memory of a deceased person whose body is buried elsewhere.
An easier definition of cenotaph is a headstone or monument for someone who isn’t buried (including inurnment, scattering of ashes, entombment, etc.) next to the headstone or monument. Often, they are not in the same cemetery.
Here are some Find-A-Grave Forums answers on cenotaphs – you will need to a Forum member and logged into to see the links below:
Basic question about merging cenotaphs. The response was cenotaphs aren’t merged. However, the question didn’t make it clear if they were talking about merging cenotaphs with other cenotaphs (same cemetery or different cemeteries) or if they were talking about merging a cenotaph with a known burial location. For same cemeteries, the rules are different as a person can only have one memorial in a cemetery. The exception would be if somebody had remains in different graves in the same cemetery. For example, Mary Jones was cremated and part of her cremains were buried with Husband #1 and the other part with Husband #2 who are both in the same cemetery. The response was clarified by this answer: https://www.findagraveforums.com/topic/17505-cenotaph/ (at least in the case of an actual cenotaph vs. separate burials / inurnments in the same cemetery).
However, in this case, the two memorials were merged – https://www.findagraveforums.com/topic/17470-person-with-two-memorial-in-the-same-cemetery/ – it’s possible the woman was split among the two graves. Even if she wasn’t, the last names are different and it becomes a question of where she is buried since the last name on the headstone would take precedence according to Find-A-Grave rules. I realize she married the second husband after the death of the first husband, but that doesn’t mean she was buried with the second husband. I ran across a woman who had three headstones in different cemeteries spread across one state. She was buried with the first husband and the other two were cenotaphs. Locally, a woman was buried next to husband #1 under his surname although she remarried after he died, and originally had the last name of the second husband on her memorial.
For Find-A-Grave, you have to request a memorial be designated a cenotaph. How long it takes depends on how far behind they are on approving cenotaphs or other edits. Also, normally you don’t link a cenotaph memorials to parents or link children to a parent’s cenotaph. The exception is when there is no known burial location for the individual. In a local Wichita cemetery, the headstone is a cenotaph for somebody who went down with his ship during World War II. His body was not recovered.
BillionGraves allows the addition of multiple records in the same cemetery. However, if the birth / death dates are the same, they may be merged which can cause problems finding the other memorial(s) as the GPS will show for only one of the memorials in the case of somebody having multiple headstones in the same cemetery. In a different cemetery, an individual has two double headstones as they had two spouses. I have no clue as to which one the individual is buried beside. In the case of different surnames, like the one above in the last paragraph, the records would not be merged.