Prolong? I don't know, since I've never done it, but I imagine that sending a copy of the obituary as proof might be enough. I mean, compared to leaving it up indefinitely, it seems like contacting facebook could help forego continued agony. I don't know if you've ever had to be the bearer of bad news, but as you might imagine, it really sucks to tell people that someone has died but after a while (in my experience) one comes up with kind of a template to go about telling people what happened. Unfortunately, it's just one of those things that people have to do when someone dies. In the situation I'm talking about, it's still up and people are still posting to it. This happened sometime in the summer of 2012, to put it into some context. To me, it seems like just knowing that I could visit a facebook page instead of having to get up and go to a grave to sit and remember a person and maybe chat with the headstone/marker seems like a very real kind of temptation that I don't care to indulge myself in. Of course, I'm speaking as a person where part of my cultural funerary tradition involves visiting the graves of those near and dear on the anniversary of their death, cleaning the gravesite and spending the day with others who have come to pay respects.