Looking into Merkel’s genealogy taking in account what Q said about German naming customs. Attached is a link that explains the customs, but basically it involves naming a child after father/mother, paternal/maternal grandparents, and so on.
rieperoots.com/pages/Names/customs.htm German naming customs
One theory is that Merkel was the daughter of Hitler by Eva Braun’s sister. Eva Braun (b. 1912) had 2 sisters, Ilse Ruth (born 1909) and May Gargarethe (Gretl) Braun (born 1915). Gretl was not Eva’s twin sister but her younger sister. Gretl was married to SS-Gruppenführer Hermann Fegelein.
https:// en.wikipedia.org/wiki/Eva_Braun
https:// en.wikipedia.org/wiki/Gretl_Braun
Checking the family names of the Brauns, there are no Angelas or Dorotheas on either side, as far back as the great-grandparents. The genealogies are rather muddled online; different names are given for the same grandparent. One possible great-grandmother is Dorothea Weidemann but Anna Erhardt is also listed as that great-grandmother. So based upon the German naming customs, I’d say that Gretl Braun is not a good candidate for Angela Merkel’s mother.
Another theory is that Merkel was descended from Hitler via his half-niece, Angela (Geli) Maria Raubal (1908-1931). I have linked to a brief genealogy of Hitler’s family here. >>616757
Geli lived in the Hitler household and committed suicide at age 23. She was reported to be extremely close to Hitler. If she did have a child by Hitler, and it was given away for adoption, that child would have been old enough to parent Angela Merkel.
Angela Merkel’s parents are Horst Kasner and Herlind Jentzsch. Kasner’s genealogy is not too hard to find on the internet. There are no Angelas or Dorotheas that I could find on his genealogy. Herlind Jentzsch was born in 1928 and her birthplace is listed as Gdansk (Danzig), Poland. Her genealogy is a bit harder to trace. Her parents were Gertrud and Willi Jentzsch, and she was an only child. So her birthdate would be in line with a possible birth of a child between Adolph Hitler and Geli Raubal.
As much as I could find on the Jentzsch/Drange family, which wasn’t much, there were no Dorotheas or Angelas. I also could not find out what Herlind Jentzsch’s full name is.
However, it can be seen that Angela (Geli) Maria Raubal was named after her mother (Angela Farazska Johanna Hitler Raubal) and her paternal grandmother, Maria Pichler. If Geli had a daughter named (perhaps) Dorothea Herlind, then it could be possible that Herlind’s daughter could be named Angela after her grandmother. In which case, Herlind would have been adopted by the Jentzsch's.
So…based on Q’s clue of German naming customs, if indeed Angela Merkel is descended from Hitler, I believe that it would be more likely to be as a granddaughter via Geli Raubal than through Gretl Braun (artificially inseminated by Hitler’s frozen sperm).