glee 315 big brother spoilers.......warming Almost the whole cast have already shoot their scenes includingDianna Agron but we still don’t know what hers will be about. As you already know Matt Bomer will be appearing as Cooper Anderson, Blaine’s brother. The two brothers will be involved in a flashback. The crew has already picked the two kids who will be appearing as the mini-me’s of Blaine and Cooper, but we still don’t know who they are. Matt Bomer already recorded two songs for this episode and one of them will be a duet with Darren Criss. The duet will be a mash-up of Duran Duran. It could be: Girls On Film / The Wild Boys Ordinary World / Planet Earth The Reflex / Is There Something I Should Know We will not just meet his brother but his father too and possible other members of the family. We still don’t know what this has to do with this tuesday’s episode, but we will soon.