Spoiler: I mean yeah, I have considered that stuff. I'm just not totally sold. especially because we don't know the birth order in regards to the third kid, so the second thing is pure speculation just like the theory. it's kinda hard to guess based on what we've seen and do know--like, Todoroki's 15, and the other brother is 19. lotta room in there for the third kid to be between that brother and Todoroki, you know? I will say if it is Dabi, the original hair color continues to match Quirk, though. in our singular screenshot of that kid, his hair is red, which means it'd fit for him to have a fire Quirk. even if he dyed his hair later. eta: basically, I am not saying it's impossible. I even think it could be plausible. I also think it would be interesting. I just also think there is reasonable doubt to be had.