i like the idea that it's understood in the Batfam that Bruce has a favorite but no one's really sure who it is-- all of them have their own guesses, and it's never themselves (except Steph, who's here to laugh at their theories)
Dick is convinced it's Jason because of how he saw Jason's death destroy Bruce-- like, he knows Bruce would cry for all of them, mourn and all, but... well, he's pretty convinced Jason had a spot in their dad's heart a bit bigger than they did
Jason, if asked, will swear to hell and back it's Dick-- the Golden Boy, the perfect son, the one he had to compare himself to growing up. Secretly though? he thinks it's Tim. Tim, the best detective of all of them, the steadfast kid who stepped in to fix everything without the slightest bit of thanks or appreciation, the nerd who dedicated himself to their crusade with nothing to gain from it. who wouldn't favor that kid??
Tim has known since the first picture he ever took of Batman and Robin who the favorite was, and has never wavered. Dick Grayson, his first son, the one who's pain was reflected so sharply back at him in a twisted mirror that he had to take the kid in-- Dick was the one to bring the Dark Knight to life in the daytime. Dick is his everything-- the boy he loved enough to slow in his life's work to help. Tim was certainly never worth the time, but Dick? Dick is impossible not to love, and to love Dick Grayson is to love with your whole chest
Cass bases her guess off of Bruce's body language, not Batman's, and for that, she thinks it's Duke. Duke is softer than the rest of them, less sharp edges from a childhood shaped by misery or death, and Bruce is less of a drill sergeant with him for it. after all, Duke doesn't struggle with directions like the rest of the Batfam (he so does, he's just the best at hiding it), so he gets less of the terrified, furious leader and more of the tired, worried dad
Damian has no doubt in his mind it's Cass-- at first, because she's the best fighter, and therefore most deserving. she's far more skilled after all, so in this insane family where adopted children upend the hierarchy he knows, it must be dictated by skill, no? no, actually. but then, he sees how Bruce doesn't yell at her, the implicit trust he has in his daughter. the way that they're so very in-tune with one another, it's like looking at a man and his shadow. Cass has to be the favorite, because no one else can look him in the eyes with the same sort of heartbreak he has and comfort him without a word
Duke was an only child before joining the Waynes, so it was a shock to suddenly see sibling favoritism so blatantly when Bruce so carefully and kindly talked Damian down from a rant about his classmates in the middle of patrol. no one else would've been allowed to talk about something so personal and revealing on a Gotham rooftop. it was just continually proven from there; shoulder pats and hair ruffles answered with little scowls, utterances of "son" that were lost to shuffling capes and tiny smiles tucked away in darkness
