The analyses of a text #5

The narrator recalls his childhood; now he came home from the boarding school for his mother's sudden death.
Peggoty is the only maid of his house.
.......................................
In these days before the funeral, I saw but little of Peggotty, except that, in passing up or down stairs, I always
found her close to the room where my mother and her baby lay, and except that she came to me every night and sat by my bed's head while I went to sleep.
[David Copperfield by Charles Dickens]
I'd like to know if "in passing up or down stairs" modifies "Peggotty."
And I'd like to know if "that" is leading "I always hound her close to the room where my mother and her baby lay."
Thank you in advance for your help.