Bad Brother!

Question
I have three ferrets.  One 1yr old male, one 10mon female and one 4-6mon male.  The newest one, Leo is the youngest and we got him about 2 1/2 months ago.  The eldest male, jack, will not be nice to him.  When we first brought him home, jack bit his neck hard and would drag him around, which my boyfriend and I supervised and broke up when leo got stressed out.  But then it got to the point when jack just would not let go.  He would clamp down on leo neck and we would have to pry his jaw open, which worries me, I dont want to hurt him.  So over the next month we have had little playtimes with one of us always holding jack.  when jack manages to get away he just beats the crap out of leo.  Leo is a marshall ferret and now is big, but is just such a sissy.  They still dont get along, they cannot play together because jack just wont stop biting him and not letting go for the life of him.  The female get double play time because she gets along with both of them.  Ive switched the beds, washed them all so the scent is less.  Ive tried almost everything I know.  I just would really like ANY advice on how to get them to coexist.  Please, how do I get my ferrets to accept each other?

Answer
Ferrets fight.  The only thing you can do is to let them fight.  The more you separate them, the more intense the fighting will get.  Unless there is blood, don't pull them apart!  It may seem to get pretty rough, but ferrets have really think skin and can take quite a lot.