Michael Bluth is the second oldest Bluth son, but the most competent one.  When George Sr. went to jail, it was Michael who was stuck running Bluth Company and keeping the family together.  Michael's wife, Tracey, died of ovarian cancer two years prior to the first episode and left him to raise George Michael on his own.

Michael Bluth Quotes

Michael: (to George Michael) I'm gonna give you a promotion. Welcome aboard, Mr. Manager.
George Michael: Wow! I'm Mr. Manager!
Michael: Well, manager. We just say manager. And you can hire an employee if you need one.
George Michael: Do you think I need one?
Michael: Don't look at me, Mr. Manager.
George Michael: Right. It's up to me now. I'm Mr. Manager.
Michael: Manager. We just say, uh --
George Michael: I know, but you just said --
Michael: Doesn't matter who.

Maeby: Do you guys know where I can get one of those gold necklaces with a "T" on it?
Michael: That's a cross.
Maeby: Across from where?

Arrested Development Quotes

Okay, we are just about ass-to-ankles back here, Maeby. Do you want to hop on your cousin's lap there, please?

Tobias

The zero hour, Michael. It's the end of the line. I'm the firstborn. Sick of playing second fiddle. Always third in line for everything. Tired of finishing fourth. Being the fifth wheel. There are six things I'm mad about, and I'm taking over.

Gob