Is he an agressive dog?

Question
We took in a 4 y/o dog that is well trained His old owner had passed away 3 months ago. He has been a "wonderful" dog. To our kid's and everyone he meets. He even listens to everything we say only after a couple day's of us having him. He even follows us around off leach in public and great with other dog's. He has been more then the perfect family pet. Except for one thing, he has been growling at our cats. One cat more then the other because she thinks she is boss. Our younger cat growls at everything new until she gets used to them. She still growls and hisses at our other dog who she's been w/ for 5 yrs. Our older cat doesn't care about anything and is just around!
Well last night the dog was laying down beside us. My older cat (the sweet one) Minding her own business as usual. Walks slowly threw the living room from a far distance not even looking at the dog. He sat up and watched her walk threw then slowly he stood up and started walking even slower towards her. She turned and looked at him like she was going to sniff him. Then he started growling really loud. She got scared and backed away hissing. He jumped at her and they fought a little. Our younger cat hear's this and comes flying out of the other room and jumps on "OUR OLDER CAT?" After realizing it was her. She turned and jumped on top of the dog. I yelled "no" he turned away and came over to us. My younger cat still pissed off started howling at the dog walking over to keep fighting. He turned right back and went after her again. They didn't hurt each other thank god and Again after we yelled "NO" He stopped and came over to us but hovering the ground looking ashamed he did this. He walked over and sat down, looking scared like he thought we were going to hit him or something. The family of his old owner told us that he has never shown aggression ever and that he has always been the sweetest dog? This confuses me and makes it hard for us to figure out what we should do? He still all day while laying down shows his teeth to the cats every time they walk by. One person told me I should squirt him with a water bottle every time he shows agression and praise him when hes being good near the cats but he already is very afraid of the water and I dont want to make that worse. He also shows alot of jealousy. He wants to be the only one being loved. If my husband and I are hugging when he comes home from work. The dog squeezes between us and pushes us apart wgging his tail to be the only one getting loves. He does the same thing if were holding our children (all age's under 4) he will stick his head beween my arms pulling them apart from holding our boys. But then again. If the boys are fighting he even goes over to them and will squeeze between them to get them to stop?  
Do you have any opinions or idea's besides "get rid of him or our cats?" because we really do love having him.


Answer
Hi there,

It doesn't sound to me like your dog is aggressive, he did stop after all when you said "NO", and he seemed to know that it was a mistake. It's not uncommon for a dog to want to chase a cat, and if the cat bolts, chasing it is an uncontrollable response.

Most dogs can be taught to tolerate cats if their owners are willing to be patient and consistent. Some dogs take longer to train than others and the difference is usually due to the dog's level of "prey drive".

Nature designed dogs to be predators, and to chase and catch smaller animals for food. Although dogs have been domesticated for thousands of years, they still act upon the instincts nature gave them.
A dog's instinct to chase and catch something is called his "prey drive". Throw a stuffed toy for a puppy and watch his prey drive in action as he chases it, catches it, then shakes it to "kill" it. Breeds and individual dogs vary in the intensity of their prey drives. Some breeds were created specifically for killing other animals. Most terriers, for example, were intended to kill rats, have very high prey drives.

There are several effective ways to train a dog with a high prey drive to live peacefully with cats. It's best to teach a dogs that cats are off limits altogether, and are not to be disturbed.
Using a friend or family member to help you, set up several short daily training sessions. With the dog wearing his collar and leash, have him on a sitting beside you. Have your friend hold the cat on the other side of the room. Your dog may be very curious and even excited at seeing the cat, but insist that he remain in the sitting position. Praise your dog for sitting calmly.

Have your friend bring the cat a few steps closer. If your dog continues to stay quietly at your side, wonderful! Praise him for it. If he tries to lunge at the cat, though, give him a stern, fierce-sounding "NO! LEAVE IT!" along with a short, sharp jerk on the lead and put him back in the sit-stay position. As soon as he is sitting calmly again, praise him sincerely. Continue bringing the cat closer, a few feet at a time, repeating the corrections as needed and making sure to praise the dog when he sits quietly and ignores the cat. Have patience, depending on the intensity of your dog, you might only be able to gain a few feet each session.

When your dog is able to sit calmly even when the cat is right next to him, you're ready to proceed to the next step. Let your dog walk around the room with the cat present. Leave his lead on so you can easily catch him and give the necessary correction if he gives any sign of wanting to chase the cat. Your supervision at this point is critical - to be effective, you must be able to correct the dog each and every time he even thinks about going after the cat. If he's allowed to chase her, even once, he'll want to try it again and you'll have to start your training over from the beginning.

Some dogs learn quickly, others may take weeks to become trustworthy around cats. Until you're sure the dog will remember his training, don't leave them together unsupervised! While you're in the process of training your dog, leaving his leash one all the time will help.

Offering the "correction" with the water spray and giving praise when your dog behaves is another good method of teaching your dog right from wrong. Still, your dog should wear his leash in the house so you can stop him, should he take off after the cat.

The jealousy is another issue. If your dog is not allowing your family members near you, then that could very well be a dominance issue. Your dog considers you to be the alpha dog and thinks HE is second in command, so he believes that everyone else (your husband included) is beneath him in rank.
If a jealous dog deliberately blocks the path of a family member towards you, move the dog and let the family member near you.
A crate is also a good tool to use. A crate is a safe place that you may use to put your dog in "doggy time out." When the dog exhibits jealousy, put the dog in the crate for 30 minutes.

Make sure you continue to give your dog plenty of time and attention. Show him that you love your husband, but you love him too. Make sure your husband is taking an active role in pet care, by feeding and walking the dog. If your husband could take the dog to an obedience class, that would put him (your husband) in the role of a pack leader who must be obeyed.

If it doesn't seem like things are getting better with your dog's jealousy issues, or he starts getting aggressive with your husband, then you need to consult with a dog behaviorist.

Best of luck,
Patti