Hel-loh "Annyong" Bluth is the adopted Korean son of Lucille and George Sr. Annyong was adopted to improve the image of the Bluth family. Eventually it is revealed that Annyong actually called the SEC at the end as revenge for himself and grandfather.
Maeby: You don't have to worry so much. I mean, obviously your dad doesn't want to spend time with you, but, you know, go to the beach or whatever.
George Michael: He's just not around, ok?
Annyong: He no have father? Old lady adopt him, too?
Maeby: No, he have father. Father no love him.
Maeby: Who's this?
Buster: Oh, I'm sorry. This is Annyong.
Buster: My mom bought him. She's making me register him for school. He's my new little brother.
Maeby: So, we're related. Hey, do you want to go to a dance?
George Michael: Oh, great, another uncle to compete with.