Connie, by correcting the behavior is that not establishing leadership in this instance? Or are you just trying to clarify to Ira what this behavior actually is?

 Quote: peter meaden

Connie, by correcting the behavior is that not establishing leadership in this instance?

Yes.

I thought from what I was reading that the behavior had been allowed to continue, maybe with "negotiations." The phrase "just about gotten him out of that habit" made me think that the senior was not being protected and that the puppy was only slowly or gradually being convinced that he was not allowed to do it.

I don't understand either why the pup isn't simply removed from the situation.

Dog-dog aggression is absolutely forbidden in my house. And as Cameron said, "I would only be playing with both when both dogs are under total command." That would preclude playing with both if I did not have the control over the puppy to ensure that the senior was safe from aggression. And high-level corrections on a pup aren't the way I'd go, either. I would simply end the problem situation (while working with the pup on his own). Why do they have to be in the situation?

 Quote: Ira Victor

Because I don't know as much as I should about a lot of things, including corrections. Up until now, I've been correcting him too gently, but he's too hard for that. I've been getting tougher myself, shaking his neck and making him yelp, and it's really helping.

This is a great way to squash your dogs trust in you and cause some serious road blocks in your later training.
I'm not trying to start a quarrel here, but for puppies you lose SO much of your drive and trust by correcting them at this stage. Why not set up a situation where no corrections are necessary? Why do you HAVE to have two dogs out to play? That makes no sense to me. It's not fair to the dogs at ALL. Their behavior is telling you this. Why not use it as an opportunity to mold what you DO want rather than focusing on what you DON'T want. Play should be play and worl should be work. If you have to correct to play, you are taking a lot of drive and potential away from that play session. The dog is NOT learning boundaries, it's learning that you don't play by the rules. Since (according to your earlier post) your older dog is allowing the younger to be in charge (which is way unbalanced - a pup no matter HOW hard doesn't have the life skills to be in charge) that means that if your pup wants to take the ball - it CAN. That is the benefit of being in charge. Correcting for that behavior will only INCREASE the jealousy and when your pup gets a little more dominant with age, it will increase the aggression and cause some serious problems. A lot of times having multiple dogs out to play at the same time is more for the benefit of the HUMAN not the dog.

 Quote: connie sutherland

I thought from what I was reading that the behavior had been allowed to continue, maybe with "negotiations." The phrase "just about gotten him out of that habit" made me think that the senior was not being protected and that the puppy was only slowly or gradually being convinced that he was not allowed to do it.

You were right, up to a point. I was protecting the senior, but I just wasn't doing it convincingly enough to stop the behavior permanently. No "negotiations", but a lot of frustration. Then I found this:

http://leerburg.com/hardpuppy.htm

My pup isn't the hardest in the article, but he needs more than an average correction. Even then, he never becomes withdrawn and once I show him I'm not really mad, he licks my face and he's ready to start playing again, so I don't think I'm overdoing it.

With all due respect to Cameron,

 Quote:

Why not set up a situation where no corrections are necessary? This is a great way to squash your dogs trust in you and cause some serious road blocks in your later training.

That sounds a little idealistic, at least for my world. We're a family, and we have to learn to get along. Maybe I'm wrong, but keeping them separated seems like it would hinder their bonding, not help it. And I don't think I'm "squashing" anything, I think I'm doing what his mother would do.

If I'm wrong, I'll let you know from the emergency room

That brings up my next quetsion Ira.

Is having your dogs together at all undesirable until they are both very well trained, or is it just that toys are involved?
Do the toys make all the difference?

 Quote: peter meaden

I have three dogs and put out 4 toys in order to give all dogs a toy, however my puppy (8 months) typically only wants the one another dog has. I get the point though...I'm going to play with them one at a time from now on to avoid this problem, and I can see that it will only serve to strengthen my dogs interest in ME.

Peter,

Most definitely it will strengthen bonds with you. If you have two that can play together "nicely" that is great.
Like was stated somewhere here (by Cameron I think), it is about control.
One of my dogs cannot play well with others, so we play together.
She is very obedient and gets along with the other dogs, but her prey/play drive is very high and it seems like she cannot help it sometimes.
So, it just is managed. Not sure corrections would work, IMO, it might make it worse and then she would not get along when she is just out and about with other dogs.

 Quote: peter meaden

Is having your dogs together at all undesirable until they are both very well trained, or is it just that toys are involved?
Do the toys make all the difference?

Fetching toys makes all the difference. They get along great and he doesn't try to prevent her from doing anything, including playing quietly with the toys, but if I throw one for her to fetch he has to butt in.

They really do get along well. This is the only thing about their relationship I don't like. He keeps lying down with her throughout the day to lick her face and/or play gently with her. She'll lick back, and they'll be happy, but as a pup, sometimes he escalates it a little too far. When that happens, she'll get up and come over to me, as if to ask me to get him to stop. I tell him, in no uncertain terms, to leave her alone and he usually does. It's the "usually" I was referring to earlier when I said he sometimes bites her too hard.

But just since yesterday, when I started escalating the level of my corrections, he seems to be getting the message. This morning he started getting on her case again, so I said, in a sharp voice: "Leave her alone!" and he did. He walked away, picked up one of his toys, and came to lie at my feet to chew it.

I actually did the right thing in the very beginning, without realizing it, but the more I think about it the more I understand. When I first got him, he would gobble his food up and immediately run to her bowl, push her out of the way, and start to eat her food. Without even thinking, I grabbed him by the neck, pulled him away from her bowl, and held him down until he stopped squirming, all the while telling him that wasn't his food. He didn't understand the words, but he understood the principle. Ever since then, when he finishes eating, he'll sit/stay at his bowl (without being told) until she finishes and walks away, then he'll run over to check her bowl.

I think keeping them separated and working with them one-on-one is completely unnecessary at this point. It seems almost like putting someone into months of psychotherapy just because they haven't learned to get along with their new step-sibling yet. Sure, he's the dominant one, but he's a puppy, exuberant, full of energy, pushing boundaries to see what he can do. I think I can solve this with the right amount of correction, no psychotherapy necessary. I wasn't sure about this when I first posted yesterday, but the last 24 hours have made me more sure.

 Quote: ira victor

I think keeping them separated and working with them one-on-one is completely unnecessary at this point. It seems almost like putting someone into months of psychotherapy just because they haven't learned to get along with their new step-sibling yet. Sure, he's the dominant one, but he's a puppy, exuberant, full of energy, pushing boundaries to see what he can do. I think I can solve this with the right amount of correction, no psychotherapy necessary. I wasn't sure about this when I first posted yesterday, but the last 24 hours have made me more sure.

You are looking at this from the point of a HUMAN with human "psychology".
You are not hurting his feelings or putting him into psychotherapy because they cannot get along, you are doing what they would prefer ANYWAY. If the older dog is already getting cranky and the pup is taking toys, separate them! They will bond BETTER later because the pup will learn self control and will learn to bond to YOU not the older dog! The most important thing to worry about here is whether or not the dogs bond to YOU not one another.
The more you describe your pup as "hard" the more I shake my head. You post a link to an article talking about how to correct a hard pup, but you are missing something here. Your pup doesn't NEED to be corrected for this! You are creating a situation that doesn't need to happen in the first place, then correcting the pup for acting like a pup.
Please take some time to read more about raising the pup. It will really help you in the long run.

 Quote: Cameron Feathers

They will bond BETTER later because the pup will learn self control and will learn to bond to YOU not the older dog! The most important thing to worry about here is whether or not the dogs bond to YOU not one another.

They HAVE bonded to me, and not one another(Edit: they,ve bonded together, too, but both see me as the alpha). I'm sorry if I gave you the wrong impression, but your advice seems to be based on two dogs that don't get along, or are bonding without me, or have deep-seated problems together or something similar, whereas that's not the case. I'm talking about a specific set of circumstances.

With all due respect, I think you're reading too much into this.

 Quote: Ira Victor

I think keeping them separated and working with them one-on-one is completely unnecessary

You are saying that working separately with a 4.5-month-old pup is unnecessary?