Book request: vampire descendant turned to save their life

Hi,

I'm looking for a book that includes a very specific vampire trope.

An ancient vampire finds one of their own descendants who is dying (illness, injury, etc.) and turns them into a vampire to save their life.

I’m specifically looking for stories that include both:

– a bloodline/descendant relationship

– and turning them to prevent death

If anyone knows a book with this trope, I’d really appreciate it!