When the blood clan fought the celestial race again, and both sides suffered heavy casualties, that's when the celestials brainwashed other races to shut out the blood clan.
In this kind of situation where the whole world is against them, how could the blood clan easily find someone to be turned into their family member?
That's almost impossible, okay?
Because of this, the two elders felt that if they didn't have any new blood, they had to revive the older generation to keep their military strength at the peak.
To be honest, Lyod and Caroline were also not the only ones with the special abilities to revive the blood clan members.
In previous generations, maybe once every few thousand years, there would always be a new generation who inherited this special ability.
But this means the older generation would have died already.