Given that we now know who Gerry's father was, and that Mary did kill him and use him for her book, how much do you want to bet that the page Mary gave Gertrude contained him? I could totally see her tormenting Gertrude with her dead colleague, and refusing to let Gerald be influenced by her disposable experiment.
I’m pretty much certain this is exactly what happened. More than that, I have a suspicion that he might have been one of the few colleagues Gertrude liked. Her loathing of Mary and her conflicted feelings about Gerard make so much more sense this way. On the one hand, Gerard was a big part of the reason her colleague died. On the other hand, he was an infant at the time, and Mary was the murderer. Gerard was raised knowing his mother murdered his father for the hell of it, and was taught to see this as the way things went. And he still wanted to find his father. He was still disappointed when he didn’t get to meet him in the book.
Which makes me wonder why, if this is true, Gertrude never gave him that page. Did it really fail, and she didn’t want to just show him his father’s skin and the lack of any meaningful interaction? Was she keeping that page for something else? Did she already burn the page, having realized her former colleague was trapped and suffering? We don’t know.
We do know that the way Gertrude treated Gerard is the very definition of conflict. She took him on and helped him at his worst, but she also kept things from him and bound him to the very book his mother was trapped in as well. She left him as essentially a hint system for the next archivist, denying him his humanity and his dignity. She abandoned him, and that was what hurt him the most.
So, yes, I’m almost certain the page given to Gertrude was her former colleague and friend. And Gerard ended up paying, in some ways, for everything Mary did to that colleague.













