Twin

Twins were two siblings born at the same time from the same parents. Luke Skywalker and Leia Organa were the twin children of Anakin Skywalker and Padmé Amidala. Other twins included Tiplar and Tiplee, two Mikkian Jedi Masters who fought in the Clone Wars. A clone was also the twin of their template, since the two shared the exact same genetic pattern. As such, Boba Fett was both the adopted son and twin of Jango Fett. Ciena Ree was the twin of Wynnet Ree, but the latter died a few hours after they were born. Despite never knowing her, Ciena vowed to live her life for the both of them and would think of Wynnet often.

Ben Solo and Rey were not twins by blood, as the former was a Skywalker and the latter a Palpatine. Moreover, they were born a decade apart. Nevertheless, a unique bond existed between them, making Solo and Rey "twins" in the sense that they were a dyad—two beings who were one in the Force.

There were rare kyber crystals that were connected through the Force. Jedi Wayseeker Gella Nattai owned two lightsabers with twin kyber crystals. When Axel Greylark stole one of the lightsabers, Gella was able to sense its crystal through the other crystal's connection with it and find Axel on Dalna.