Yeah, it is strange that Raditz is so 'forgotten' even though he's Goku's brother. Furthermore, even when Bardock has a highly developed fighting spirit, Raditz totally hasn't. He also doesn't share Bardock and Goku's appearance and voice.
These things, as well as his ommital from the Bardock special, indicate that Raditz being Goku's brother was a plot device discarded after Raditz' rather brief appearance.
For all we know, Raditz may have been lying about being Goku's brother, trying to convert him more easily. Or he could have been Goku's half-brother or cousin - having no relation to Bardock.
Origin of Bardock family picture?
Thats doubtful, after all most Saiya-jin were "bad guys". And Bardock neglecting Raditz due to evil intentions is also doubtful, Bardock neglected both Raditz and Goku due to his severe addiction to fight. He only started noticing Goku more when he gained the mental images of his death. Appearance wise, maybe he looks more like his mother, but thats nothing but speculation.
Those wise would consider Raditz as Goku´s real brother, since Bardock story was more likely made out of Toriyama´s hands. Even that special episode is not too much animated, lots of still scenes more like art them action. Raditz episodes was more like the real thing.
But truth is, the way the series shows us and that specific forgetting matter, Raditz could be any brother at all, you know, from the brotherhood. We don´t know how saiyans used to live besides the society was at monarchy. Remember the saiyans was stupid monks and the tsufurus was more intelligent.
But truth is, the way the series shows us and that specific forgetting matter, Raditz could be any brother at all, you know, from the brotherhood. We don´t know how saiyans used to live besides the society was at monarchy. Remember the saiyans was stupid monks and the tsufurus was more intelligent.