When Raditz and his fellow Saiyan conquerors Vegeta and Nappa arrived on Earth at the start of Dragon Ball Z, it was assumed for years that those three, in addition to Goku, were the last survivors of their race before their home planet was destroyed by Frieza.
However, sometime after the defeat of Majin Buu, it was revealed that another Saiyan had survived the planet's destruction and, in a more shocking turn of events, that the mysterious survivor was actually Vegeta's long-lost brother Tarble. While Tarble's place in the franchise's canon was debated among fans for years, it seems Vegeta's younger brother is officially part of the main continuity.
Tarble was introduced in the 2008 film Dragon Ball: Yo! Son Goku and His Friends Return!, based on an original story written by franchise creator Akira Toriyama. Set two years after the defeat of Majin Buu, a banquet held by Hercule Satan to commemorate the opening of his new luxury hotel is interrupted by the arrival of Saiyan spacecraft. Emerging from the ships are Vegeta's younger brother Tarble and his wife Gure. It is revealed that Tarble was considered significantly weaker than the rest of his family and sent to a faraway planet of little value to the Frieza Force, inadvertently saving his life when Planet Vegeta was destroyed. Tarble requests his brother's help in dealing with two Frieza Force officers menacing Gure's planet, with Goku handling the enemies with ease.
Yo! Son Goku and His Friends Return! was created as part of anime celebrations for the 40th anniversary of Shonen Jump along with a new One Piece movie. Because of the unique nature of the film, it only received a limited release in its native Japan and, beyond this, only appeared among the special features for the home video release of the subsequent 2013 film Dragon Ball Z: Battle of Gods. The film has yet to receive an official English language dub. Because of this, and due to the vast majority of Dragon Ball Z films being considered non-canon, Tarble's official inclusion in continuity was in doubt for years.
While Tarble himself hasn't visibly appeared in other canon Dragon Ball stories, he has been specifically mentioned on at least two occasions. During Battle of Gods and its adaptation into Dragon Ball Super's opening story arc, after the Z Fighters learn that the energy of six Saiyans is required for a ritual to unlock the Super Saiyan God transformation, Bulma suggests contacting Tarble. However, Vegeta reminds her that he's on the other side of the cosmos, with his exact whereabouts unknown. In the flashback sequence to Planet Vegeta's destruction at the start of the 2018's Dragon Ball Super: Broly, Nappa wonders if Tarble is safe, though a young Vegeta appears thoroughly unconcerned over his brother's fate.
With Broly written by Toriyama, rather than simply receiving a story credit as he had for Yo! Son Goku and His Friends Return! and Battle of Gods, Tarble is more explicitly cemented into Dragon Ball's official continuity. The character's sole appearance may just be a part of a limited-release Shonen Jump anniversary special, but this hasn't stopped Tarble from properly integrating into Vegeta's family, even if the elder Saiyan Prince is less than enthused to be reunited with his little brother. And while Vegeta may be in no hurry for another family reunion, the door is always open for Tarble's potential return.
