Can a vampire take elder blood, use it to create a new vampire, then diablerize the fledgling?
No (And thank God). Vampire blood, once removed from the vampire, becomes inert, dead blood. While it may be used to sustain ghouls or even vampires – rumors of sealed vessels of elder’s blood circulate like wildfire through the vampiric community – such vitae cannot be used to create childer. The Embrace must be performed by a vampire using her own blood, which must be given directly to the prospective childe. Although the sire need not press her wrist to the childe’s mouth, the blood cannot come from storage, out of a squirt gun, from a bottle of wine, etc. – it needs to flow directly from sire to childe.