Catrina is old as bones. She’s the great-great-great-great-great-great-great grandmother to literally thousands of human souls. A ferocious busybody, she plays matriarch with dozens of families, and is one of the few ‘lesser’ undead remotely influential in mainstream politics.
She and Moira go back, Moira is some sort of ridiculous sub-niece eight times removed or something. She has affection for her distant kin, helping her get her clinic set up. Moira is very big on respectability politics and civic duty. The people of this city are her children, and she means to see them raised right.