What are the odds of Elena turning into a vampire at around the same age as Katherine, and what are the odds that Klaus and Elijah both knew Tatia when she was the same age as Katherine and Elena, and what are the odds that all of those doppelgangers are roughly the same age as Amara was when she became immortal
This also is the same for Stefan, what are the odds that he was turned when he was roughly the same age as Silas was when he became immortal, and what are the odds that Tom Avery (the lastest doppelganger in the line of Silas doppelgangers) is roughly the same age as Silas and Stefan?