Althildis of Coel

Althildis of's father is Coel of Meurig and her mother is Daughter of Cyllin. Her paternal grandparents are Meurig Marius Gweirdd and Julia Victoria Prasutagus; her maternal grandfather is Cyllin ap Caradoc. She is the oldest of two children. She has a brother named Lleirwg Mawr.

Althildis of's family with Marcomir of Odomir

Marcomir of and Althildis of are married (further details are not known). They have a son named Clodomir of.