Recollect, re-collect by @Ptelea.ao3
This is a long, brilliant, emotional gutpunch of a story where Jason gets whammied by a spell that makes everyone start to forget him and the Batfamily has to work together to reverse it. Really spectacular and highly recommended if you have ever loved Robin in any incarnation (but especially Jason and Dick). I sobbed my face off several times. #being robin gives him magic