[yorkietalkjilly]

I would likely desensitize him to seeing Dex playing with the toy a lot while he's right beside him in the crate with you sitting right there playing with Dex and allowing him to play with the toy and every single time Dex plays with or squeaks his toy or takes it in his mouth, Fletcher gets his very favorite treat - warm, boiled chicken as a reward. Keep the sessions extremely short and frequent.

Always take Fletcher out of the crate and take him outside to break the built-up tension the former training and desensitization will have crated in him. Throw a ball for him and allow him to get his mind off everything each training session has built up. Very slowly and over time, he will come to love Dex' play sessions with his toy and in time, you can leash him and try a short session of a minute with him on the leash out of the crate and a few feet away from Dex as he plays. Keep this first out of the crate session only 60 seconds and then take Fletcher outside and break the tension immediately once it's over.

Getting Fletcher involved in learning that he is NOT the pack leader and doesn't get to make the decisions in your family by starting him on one of the Nothing In Life Is Free programs and making him work for every single bite of food or drink of water or anything he wants for a couple of weeks to start will start to bring him around. He will begin to see who really is the pack leader and can determine who plays with toys or does anything. And he will come to see you as his lifeline - his everything. You will be gentle, patient, loving, understanding and kind and loving in all your dealings so he will come to trust you implicitly, knowing you would never scare or intimidate him, and you two will develop a strong bond during the next few months of reshaping his behavior if you handle him correctly and with a great deal of love. He wouldn't be the way he is now without a certain amount of your having lost your place as respected pack leader and so you will slowly and over time and with great patience reclaim that. Does love a strong, loving pack leader to run the show so they don't have to step in and try to run things.

Starting him on a good, working obedience training program where he slowly learns to love doing what you say and looking to you for positive reinforcement will over time also teach him to do what you say each and every time you request something or give a command. Five minutes 2 or 3 times daily will get him working and loving the positive feedback - and treats - which are just the same as loving word to dogs - he gets for doing what you ask. He'll see your pride in him. It will make him want to please you.

This will further reinforce your position of loving pack leader who gently teaches him with fun and patience what you want him to learn to do and then reward him amply when he actually does it with a treat and genuine praise. Before long, he will be happy to quickly respond to you each and every time and come to deeply respect you.

Once he comes to respect you place of authority and learns how to properly respond to what you tell him to, he will begin to bow out of his over-aggressive attitude toward Dex but it will largely depend on how much fervor and work you put into this process and whether or not you can make it a fun game to do what you say rather than what he wants to do.

Be sure Fletcher gets lots of exercise and play sessions with you during all of this reshaping of his attitude and behavior.

At the end of six to nine months, Dex should be able to play with his toys without Fletcher stepping into the process, though at times any dog will always claim his buddies' toy but you will be there to step in when you think necessary and remind him not to do it and reward him when he backs off. It won't be a quick process and there aren't any quick fixes but it will work in time.