The birth of Elena's necklace which we all now know belonged to Rebekah. This series of flashbacks were set when The Originals were just "Ordinary People" And they were one innocent normal family living in this whole different world. This scene however is when Rebekah has only just been turned into a vampire by her parents and she is looking at the necklace which eventually burns her.
I quite like this, and I also liked Rebekah back when she was in her earlier years she was more nicer than she is now :') Then again if your brother had daggered you since the 1920's I think you'd be holding a grudge against the world too.
Also, What i'd like to know is how the vampires can adjust to technology and dress so easily and not be like "Wi-Fi?! What is it?!"