I'ma gonna say this a -one a-more a-time:
Hitler's elder sister Angela moved in with him at his compound in 1925, bringing along with her Hitler's niece, her daughter, Geli, aged 17. Hitler was smitten with Geli, and after her "suicide" (possible murder) years later after failing to escape from Hitler, he fell into a deep depression, and said she was the only woman he ever loved.
Now the link: Merkel's daddy was born in 1926. The possibility is that he is the child of Hitler and his niece Geli - shot her down with the first salvo, as it were. Merkel's daddy's "daddy" was a Berlin policeman. Who wants to bet that Merkel's daddy is Hitler's son and nephew (all rolled in one)? And yes, Merkel's daddy Horst was in the Hitler Youth, but don't get excited, almost all young men and women in Germany were in the Youth Movement at the time.
In those days, it was common for an illegitimate child to be fostered out, with an appropriate payment, to a suitable family to raise and claim as their own child.
This fits. Whether it is correct or not, only a DNA test can ascertain.