The problem with the Robins in DCnU

Namely no one seems to know what they timeline is.

The worst offender is Damian Wayne. By being 10 or older he calls into question how Bruce could father a kid that old if he's only been Batman for six or seven years. According to Batman and Robin #0 he's had several birthdays so it seems unlikely for him to be aged due to whatever process Talia used. (Although the art in Ra's Al Ghuls' one shot implies otherwise.) Though there have been hints of her doing this for someone else in Batman Inc. The B&R issue also stated Damian was 10 when he met his father and it has been a year and a half since then. That statement was retracted not long after, a couple issues or so, when Bruce stated Damian was still 10.

Back when the new 52 started Jason said that he was still training with the All Caste a year and a half ago. Give or take a few months from what's listed above that would have meant B&R was saying Damian appeared before Jason returned as Red Hood. While the Damians' year and a half seems to already be ignored the mention Jason made in #2 of RHATO has been reduced more under Tynion who say Jason came back a year ago. Which makes zero sense. Things like Jasons' time spent as Robin, which used to be two years, isn't mention in the trade. Jason is younger than most people think and has actually has aged since his death. He would be 15/16 when he died so be should be 18.

Nightwing stated that he was Batman for almost a year, with Snyder insisting another year has passed since Damian became Robin that would have made Damian 12.  Time wise it's a mess but I think, for the most part, how they became likewise Robin varies.

Dick Grayson: (We'll ignore the Owl stuff.) It starts off the same with his parents falling to their deaths. To protect Dick, who witness the threats made against Haly prior to the fall, Bruce agrees to take him in for awhile. There's no mention of Dick being adopted or even Bruces' ward. He's a ward of the state that more or less ends up going to the manor for a "job." Every night Dick sneaks out in hopes of finding his parents killers. Batman knows this but doesn't try to stop him. For some reason Dick can "read" people based on how they move and figures out Batmans' ID. Batman refuses to take Dick into the field and pretty much gives him a Oracle-like job of gathering information. Dick has been putting together his own suit in secret and once Batmans' attacked he jumps into action. Seeing how determined Dick is Batman doesn't try to stop him from being his partner.

Jason Todd: The Joker sees him and decides to "create" a Robin by destorying Jasons' family or Jasons' losses his parents then decides to steal to survive. Batman happens upon him and decides to take him in. Jason has no idea who Bruce really is until he tells him, and unlike the others he offers him the job of Robin. Jason doesn't know if he wants it but gives it a try. The events of DITF are more vague than before but the search for his "real mom" and the ambassador Joker stuff never happened. How he returned from the dead is unknown to Talia (Tynion retcons this to make Talia bring him back with the pit because she's obsessed with him taking over the LOA....for some unexplained reason.)

Tim Drake: Tim has loving parents that encourage him to fullfil his potential. He's already acrobatic but the focus is still on his brains. Tim notices that Robin has disappeared and how different Batman is. He decided to look into the matter because he's worried. Alfred and Bruce know he's trying to uncover Batmans' ID. Alfred encourages Bruce to take Tim in stating Jason wouldn't want Robins' legacy to die with him. Bruce refuses and tries to get Tim to give up. This makes him take drastic measures as Tim steals the Penguins' money to give to charity. Only Batman wasn't the only one to notice and hired killers come to kill the family. His parents survive and go into witness protection. He's taken in but refuses to go by Robin in respect of Jason and Bruce (who's still grieving.)

Damain Wayne: There was nothing really to change except how he came into being. Everyone besides Morrison writes it as Bruce letting himself love Talia for the night. Talia, determined to make the perfect heir, raises him to strive for perfection. He's turned into an assassin and handed over to Bruce before Talia claims him again. Later on Dick takes him in as his Robin. Bruce returns and starts his rather complex relationship with his son.