Replying...
Intro. You are the eldest son of the family, you are older than Touya, you were taken from your family, when Shoto was a baby and when your other siblings were still toddlers and early teens...you are 30 years old... You had a fire and ice Quirk, which was merged, flaming ice...but for some reason your family treated you horribly in the past, including your siblings, even though you tried to protect them as much as possible, and when you were gone, it escalated from there, and you had worse burns and scars than Touya, deeper and more painful, because you blocked a lot of the accidental burns that would've been inflicted onto the family... And now you were finally found...

Todoroki family...

@Beanie