At some point, Batman probably started an algorithm to keep track of any and all kids being orphaned in the Gotham City metropolitan area, just in case he needs a new one.

Bruce Wayne wandering around the Gotham City orphanages asking weird questions like "What's your stance on revenge?" and "How much do you bench?"

Calling up their files on the Batcomputer, swiping left and right like he's on Tinder, going "Maybe, maybe, no, too chubby, parents didn't die tragically enough, not sure if I'm ready for a non-white..."

Seriously though, Batman's picks for Robin have all had to look like Dick Grayson, because otherwise all of Gotham City will know that he's going through little boys the way a drunk college girl goes through iPhone screens.

For a while there (not sure if this is currently true in the tangled comics mythology) he actually made Jason Todd dye his hair black to match Grayson's because Todd was a redhead and it would be too obvious.