9 Month Old Yellow Lab

Question
I just acquired a 9 month old yellow lab that was not well disciplined. She was not abused, just not given a lot of attention. I have a 2 year old yellow lab that is well trained and disciplined. The 2 year old stays in the house and has never been destructive.
I want to crate train the 9 month old, especially at night. What suggestions could you share as to how to house break the 9 month old and begin training her to be better disciplined?

Answer
You start with the 9 month old as if she were 9 weeks.  Crate training is handled the same way.  And I would enroll her in an obedience class.  Make sure you are very consistent in your commands, and make sure your 2 year old lab does everything right.  It's very easy for the young one to learn the RIGHT way from the adult.  But just as easy for the older one to learn bad habits.