Quick comment on the question of where Susan Reilly is buried. If you look at the picture posted of her gravesite, you can see a surname on a headstone in the back of that picture. On Findagrave, there is a photo for a Andrew J Hanley that looks like it could be the opposite side of this maker. The cross on top is a match to your photo. Link to Hanley's findagrave page to see cemetery and plot location.: https://www.findagrave.com/memorial/126102439/andrew-j-hanley
Given that, this Hanley could buried a few rows behind Susan Reilly. You might check that route. Just because she doesn't have a page on Findagrave doesn't mean she's not interred there. Other clues in the picture might help if this isn't a good option.
Hope you find your ancestor this weekend!