General Armstrong in game of thrones

I was re watching the episodes with the Armstrong's and got to where the sister is 'northern wall of Briggs'. Guess what else has a northern wall? Game of thrones. Where are the fanfics of her bring the warden of the north in the game of thrones? There are very few that I have found and am wondering if this idea has been used and of not, why hasn't there been one? The Armstrong's could be one of those families like the stark's as they already have the pedigree for this. Just imagine the Armstrong family in there and facing white walkers or Alex being shiny. Where are these fanfics?