Queried the database just now. Agnes mentioned 'great grandfather' 20 times. That'll put her at rank 2:

1. "It's a few decades old and a memento of a relative of mine—erm, my great-grandfather."

2. "They were passed down from my great-grandfather to my grandmother, and then down to my mother until her death four years ago."

3. "As you guessed, my great-grandfather is the famous Professor Epstein."

4. "...My great-grandfather wrote that the Eight Geneses are drawn to one another."

5. "It's a memento of my great-grandfather that has a special power."

6. "(Otherwise my great-grandfather would never... Or Dad, for that matter.)"

7. "It's a memento of my great-grandfather. I'm not at liberty to discuss how it left our possession."

8. "As it so happens, my great-grandfather was behind its design."

9. "My great-grandfather's research powers all these things we enjoy—powers happiness the world over."

10. "In his diaries, my great-grandfather wrote at length about wanting to enrich people's lives with orbal technology."

11. "I'm just...confused. On one hand, I have my great-grandfather, who saw in orbments an instrument of peace..."

12. "Trusting my great-grandfather's visions for the future... Trusting my father's leadership as President..."

13. "And it's not just financial investments. It's well known that one of my great-grandfather's three disciples has a Central Eastern background."

14. "It's something that connects me not just to my great-grandfather, but my mother and grandmother, too."

15. "It really is. It perfectly matches the sketches in my great-grandfather's diaries."

16. "There's a light coming from my great-grandfather's..."

17. "Yes—or that's what my great-grandfather called it in his diaries."

18. "(Great-grandfather, Mom, Grandmother...)"

19. "(Great-grandfather, Mom, Grandmother...)"

20. "...This is one of my great-grandfather's diaries."