There's absolutely no way the show could get away with introducing Dick Grayson (aka Robin) into the fold, considering that he's substantially younger than Bruce (up to 15-20 years younger depending on the material), and would therefore be a way off from existing in the world of Gotham. Still, we've got no qualms about the show introducing Dick's parents, whose Flying Graysons act could perhaps be sighted by Bruce during a trip to the circus. Hell, shave a few more years off the canonical age gap and have the Graysons be planning for or even expecting Dick: we'd be willing to go along with it. How Likely Is It? 5/10. This would make for a pretty great subplot in a standalone episode, and would be a blatant enough reference that even more casual viewers would appreciate it. Alfred takes Bruce to the circus, they go backstage to meet the performers, and a reference is made about them trying for a baby. It needn't be anymore complex than that, and something this minimal likely wouldn't feel forced or shoehorned into the plot.