@Riri Bulon Actually
Spoiler!
He and her biological mother is only mentioned in the story. I think her maternal grandfather died of old age so his son William took over the business. So there are no more family members from mother's side.
I like to post spoilers for the stories I find interesting because I don't have much time to read novel due to busy schedule
you will find me in most romantic historical manhwa comment sections 
you will find me in most romantic historical manhwa comment sections