I believe it is a repair, more likely a patch, from the pic. However I will go with a patch due to the number 1 in 12. The way the "paper" is working across the 1. The obvious line and almost cut out look of the work.
Looks like someone fancied themselves a conservator of some sort. I could be wrong.
Appreciate you guys that took the time to respond. Under good magnification I believe you're both right and it's a repair. Was in an album I bid on and won. Still a novice at this but enjoy the hunt and couldn't help but get a little excited at the prospect of finding an error among my new additions!