We have two puppies which are 6 months old . They are brother and sister and play very well together when other dogs are not around . When we go to the dog park and there is other dogs there our male gets upset and starts to bite . Nip and bark at the female . We have tried time out with him but then the female won/t play anymore with the other dogs . We have started to notice that the female won't evan try to play anymore with other dogs and this upsets us . We really don't want to go to the park with only one dog as we love both and would like to find a way to fix this / ANY IDEAS WOULD BE LOVELY

First of all, siblings is never a good idea to have. They don't need anyone else but each other, and this includes humans. They may interact with you and may even cuddle with you.. but they don't need you for companionship.

With that being said, it makes sense as to why your two dogs do not interact with other dogs. They simply don't need to. Intact males can be very territorial. The dog park is "his", his sibling is "his" and you are "his". I suggest to neuter him asap, if he isn't already neutered. Some males, even after neuter, will still act like a "stud dog".

You're going to have to do things separately for a good long while. Take ONE pup to dog class, don't take them together. Take ONE pup with you when you go some where and take ONE pup to the dog park.

Is this going to be forever? No.. But don't expect it to happen in a couple of weeks either. The separation and breaking of their bond can take months to years. But you have to do things separately. There really is no other way around it. Even working with your dogs together gives them the security of each other. You need both of them looking to you for security. I would even go so far as to housing them separately in separate rooms. Can you still do things with your dogs together, of course! But try and do activities, such as the dog park or obedience class alone with one pup at a time.

As things get better, then you can start doing things with your dogs together. I owned the mother and two siblings. I showed my dog all the time as did my mom with the mother dog. We still had sibling problems, but all three dogs lived their own lives with us.

Separation! Separation! Separation!

Well it sounds like the male is getting very jealous because he only wants her to play with him. What I would try is taking him by himself so he can play with the others dogs. And hopeful he will see that it's okay that she plays with other dogs as well as him.

The commotion that frequently happens in a group of dogs is upsetting to all the dogs, some more than others. The male may be displaying his induced aggression on the only other dog he is familiar with in the group, and feels dominant to.

Recall how all the dogs around a dogfight are soon engaged in the fight themselves. And aggression between two people, whether real or during play, will often get the family dog involved by demonstrating it's own aggression. Stopping the fight/play cools the dog down in both examples. It is a hard wired reaction in the dog world.

Don't attempt to understand your dogs behavior by relating it to human behaviors... it only confuses you. Dogs don't have the same emotions that we do, and operate more on the dominance/submission relationships that exist in the dog world.