One sword? Maybe ... Multiple swords???? They would never.

I see what you did there 🤣

That is probably the best option, if it is an option, and it opens some interesting implications for some vampire lore

So a new coven of young vampires is a threat to both existing power structures as well as secrecy, so there's some lore that vampires will hunt down unaffiliated vampires. Young vampires who turn many others could mean exponential population growth, and any rogue new vampire is a potential outbreak

I also like the implications of that for trope that romantic relationships are forbidden between progenitor and the progeny... It makes way more sense than hedonistic immortals have some inbuilt vampiric incest taboo

Exactly this situation makes way more sense

There's some interesting stories that could be written with this premise... It's the classic socially forbidden romance