Sisters Pits

This breed of dog should never be human aggressive, it is a major concern if one is. As an owner/breeder I have to say if these dogs have always lived outside in a run, with no family type raising they are pretty much not your typical APBT. I don't want to assume this but two male and a female is not what I would call ideal, especially in the same pen all together, your sister and her family are setting themselves up for failure.
 Could it be the bitch is coming in heat and the dogs felt threatened? If this is a sudden change in temperament and these dogs have been raised with lots of attention, socialization and training then I would consider having the thyroid checked. If they have NOT been raise with the previous then I would say that your family might try a traing class to gain what they haven't implimented.
 Me not knowing the bloodlines is a tough one, that is if they are pure bred.
 
This is not a breed you can just throw out in the back yard, breed it when you want and expect it to be like any Spot down the street, same for any breed, you MUST teach the dogs what is and is not acceptable through training and socialization, human aggression should not be tolerated. If this is truely what is happening, human aggression then it can and most likely will end in disaster.....
[sm=soap%20box.gif]
 

They live outside but they have been raised with my sisters 3 kids friendly to everyone, I will have to ask my sister if blue might be in heat or is going to be in heat, maybe that is it, they are purebred blue lived inside for the first 3 years of her life until ninja was born they lived outside but come in the house they have a big backyard they run around and also (her inlaws own the house right beside them) they go in that yard. Never had aggression toward the kids and towards any other person, blue used to come to my house and play with my dogs. What happened today was the first time they ever had aggression toward a human. 
 
The dogs were fine with people until this morning, I told my sister maybe they felt threatened maybe it was a one time thing. But I'll ask about if blue is in heat that might be the problem. They love their dogs and don't want to put them down.

I'm not expert, but it's true--and not just for pit bull and pit bull mixes, either. My dog bit my niece 8 weeks ago and that has dramatically, and I mean dramatically, changed my life--our lives.
 
I'm taking money I should be using for other things and paying to help me with him. He's not aggressive, just very shy, but as we all know, if a dog cannot behave in a safe manner, it's the dogs who suffer.
 
A coworker told me about her MIL's dog, little one, who has taken to biting her MIL with redirected aggression (somebody knocks on the door, the dog is barking, she goes to pick him, and she gets bit) and my coworker said, "Sorry, but if a dog bites me, he's on his way out of this world." I said, "Why? He hasn't been taught and neither has your MIL."
 
As Amstaffy said so nice, all dogs need to be socialized and worked with. In my particular situation, I took in a dog knowing he'd need more and more help. So far he's been to lots of training, I've introduced him to Clicker training, and upward-moving Clicker training classes, which he absolutely loves, and I'm working with a behaviorist.
 
I've established new rules for guests, for me, and for my dog, and I'm actively working to desensitize him.
 
It's going to take a long time, but that's how it goes with dogs. Mine was left in the backyard, too, alone, and I'm dealing with the results.
 
Let's see what we can do to change the pit bulls situation, if that seems possible at this point. Like I said, I've totally and radically changed here, because that's what a serious wake-up call means.

I hope that is what the issue is. I really don't want to be mean or rude but if they own three and they are left to live outside the majority of the time that is a red flag to me as owners.
This could be a warning sign of what is to come because they are not getting daily interaction, training or socialization. Pack mentality can set in and the owners are no longer the pack leader if they have to establish their own. Going out to feed does not constitute interaction in this breed.
These dogs need walking, playing and training on a daily basis to stimulate their minds and bodies if they are to be expected to be good members of society. Without this type of interaction should they get out it will be disaster

I am no expert, but I would seek the help of an animal behaviorist who has experience/specializes in Bully breeds.  Temperament testing may be in order, and if things don't go well, they may have to make a tough decision.
 
As Amstaffy mentioned, human aggression is not a breed characteristic of APBTs, and should never be tolerated.
 
Are they purebred, or mixed with something? 
 
It is imperative that these dogs experience proper socialization, and are part of a family.  Living outside in a kennel, IMO, is no way for a dog to live.  You mentioned that one of the dogs used to live inside, and that the dogs come in, but they need to be exposed to people of all kinds, and have constant interaction.

The first thing I would do is neuter the males if they aren't already.  [8|]

BRAVO Nancy!
 What a great step you have taken to better prepare your dog for the future.
 
Thank you for being a responsible owner!

They all come in the house during the day, but they sleep in the kennel and they are fed out there also, they play with the kids, they all do get walked, but this morning was different they weren't themselves. When company comes over the dogs interact with company, my sister husband didn't understand why blue and ninja did what they did to him, I am hoping that blue may be in heat or about to be and that is why that happened. Blue has always been a gentle dog ninja also even though he looks mean (lol) but he's just a big baby.  They never done this. 
 
Both males are neutered. They are all purebred. I'm going to my sister's house in the morning and I'll ask her if blue is in heat. I pray that is the problem.

A coworker told me about her MIL's dog, little one, who has taken to biting her MIL with redirected aggression (somebody knocks on the door, the dog is barking, she goes to pick him, and she gets bit)

 
Nancy--Willow does this only she bites herself.  The vet just put her on medication, PM me if you want more info for your friend. 
 
Sorry to interrupt this topic. 
 
I hope the pits are going to be able to be helped.  Unfortunately, can't offer any advice just support. 

*preparing for flaming*
 
With just the info the OP has given, I don't think that having these dogs put down is necessarily a bad thing.  Bullys should NEVER show any kind of human aggression.  These dogs are what I would consider a major liability to their owners, but also to the breed in general.  I have little tolerance for human aggression.  These dogs are obviously unstable to a dangorous level and IMHO should be put down for the safety of those around them, as well as the safety of bullys everywhere.
 
Sorry to be harsh.....

You're not going to get flamed by me, Christina.  I agree with you.

ORIGINAL: sillysally

I don't think that having these dogs put down is necessarily a bad thing. 

 
Sudden aggression when not seen prior would indicate something is wrong, as simple as a change in thyroid or a bitch in heat. These things can be controled, thyroid meds and spaying the bitch although it seems as they using her for breeding(2 litters to date).
 
If these two things are not the cause then I too would be making a trip to the vet.
 

Dogs were fine today no problems even company came over and the dogs never met them and the dogs were friendly as if what happened never did, my sister is taking Blue and Ninja to the vet also, Guess it will be a family affair at the vets office on tuesday, was monday for me but called me today and said they were closed monday lol.
 
My sister has blue and debo in one kennel and ninja in the other one. but they all come in and play out in the yard and take walks just fine, Blue was in heat last month my sister said.
 
Sally not going to slam you, if what happened to eli (my sisters husband) I would feel the same way and think about putting the dogs down. They are big dogs. But hopefully vets visit will give us some answers to why her dogs are being aggressive and why my Princess is also being aggressive.