They did. It was in the main Brightest Day series.
His surface name was Jackson, but his birth name was Kaldur. I think it must have been Arthur who told him.
As for this newest version....there's not much to go on. He can swim fast enough to be considered "unnatural" and his mother/guardian is a bigoted bitch, and he's gay.
Oh, and his hair is somewhere in between Brightest Day dreads and Young Justice crewcut.
I dont care if hes gay. Whatever. Good for him. I am a bit disappointed that his sexuality was deemed important enough to be mentioned in the....three-ish panels he got.
I mean, is it such a huge, critical aspect of his character that it was important enough to show in those precious few panels? I'd think that his father (or lack thereof) might have been a bigger character hook than "I like boys." I'd have thought a lot of things about him would be more important and worth mentioning than "I like boys." But then, straight, gay, or otherwise, I dont really care about a character's sexuality and hate seeing it made into a big part of their personality.
Oh, his boyfriend? Ten bucks says its Bunker. Gay, and multi-racial! It'll piss off all the right people.
Regardless of what they do with him, Im just happy he's back. Loved the YJ version, was satisfied with the BD one. Have high hopes for this guy, with hope that he shows up in Abnett's Aquaman real damn fast!