User blog comment:Justice Avenger/Which young heros you think should be added to The Team?/@comment-4026406-20120617031543/@comment-4928331-20120620115836

So, I guess this is how the argument went:
 * 1) Us: I want a kid Green Lantern on the show.
 * 2) Matthew: That is stupid there are no kid Green Lanterns.
 * 3) Us: Batman Beyond.
 * 4) Matthew: Doesn't count it's not a valid Universe.
 * 5) Us: Arisia Rrab.
 * 6) Matthew: She doesn't exist because I know there are no kid Green Lanterns. There is no way kid Green Lanterns exist because I'm an expert of comics and I'm never wrong.
 * 7) Us: Here are various websites about her, including a fan appreciation thread.
 * 8) Matthew: FAKE FAKE FAKE la la la la la la - Edited by Zergrinch -

In any case, Batman Beyond and Justice League Unlimited is now being published as part of the new-52 DCU universe. Like it or not, it's part of the DCU now!