Volpau

Volpau was Emperor Palpatine's third cousin, and is only mentioned in passing by Tsumo in Boba Fett: Salvage. It seems to suggest that Volpau was an assasin or something of that sort.

"Volpau, third cousin of Emperor Palpatine, died on Ubuuga of unknown causes. On his way to Coruscant for ritual incineration. You hear that? 'Unknown Causes'! Biggest killer there is, unknown causes!"