Well, just an amusing fact. Seems there is a new speculation on GD Sergei that some historians offer to us.
This is a version that Sergei was a FATHER of GDss Maria Pavlovna-younger and GD Dmitri

....due to the fact that he loved them deeply. I've heard this version from a guide in a museum, and she had no exact answer about an author of such "epoch-making"

discovery on Maria and Dmitri's father. IMHO, what stuff.