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Canine Behavior/aggresive wheaton terrior dog to dog


I have three Wheaton terriors.2 are three years old and are litter mates female and male.We bought from a pet shop.I was just told never to get liter mates. I also have a 6 year old female Wheaton terrior.they have all lived together for three years.All are neutered or spayed. We have not change our routine. In the last month the 2 three year olds have attacked the 6 year old three time, requiring treatment by a vet each time. One incident she ended up with 20 staples and stiches.They are outside chasing a squirrel and the 6 yr old sniped at the female 3 yr old and then the male 3yr old and the female both attacked the 6 year old. They are no longer locked up together. I have tried to keep them apart.I do not know what to do. I believe they will not stop attacking her.What would cause this behavior after 3 years? What should I do about it? It would break the kids hearts to give one away since each own one.

You have a pack related issue among these dogs.  At age three, the domestic dog acquires the first threshold of maturity.  These two, being litter mates, may share temperament in a way that makes them (if not equal, at least) compatible: they have (hopefully, no guaranty) sorted out social hierarchy between them.  (They have NO idea they are litter mates.)  Being of opposite sex, it's most likely the male is following the female's lead (which is common).  Perhaps on his own, he would be more placid and docile toward your 6 yo but I can't see anything from here.

The level of injury is a serious indicator of future behavior.  These two are not going to stop without professional evaluation and intervention; even then, they may not stop.  During the squirrel chase, you describe redirected aggression (6 yo "sniping" at 3 yo) and the resulting "attack" from both 3 yo dogs is a pack related social statement.  Dog to dog aggression CAN BE a precursor to dog to human aggression, and usually it's a child that suffers.

Keeping them apart is not an option.  Those two WILL find a way to get to the 6 yo and may likely kill her.  You have two options:
1.  Find a certified applied animal behaviorist in or near your area (and check credentials, anyone can call themselves anything), hopefully from one of the two sites below:

It will be a lengthy process of evaluating each dog individually, observing the two 3 yo together, then observing body language among them when the 6 yo is introduced.  It SHOULD also involve interviews with the children MINUS their parents (you'd be amazed at what children say during such interviews).

Since this appears to be "on sight" the prognosis is not good; let's say, it's guarded.  It's going to take a lot of work and if your children are young (under age 12) they will not be able to fully participate, leaving the dogs at risk of getting together with a seriously bad ending (including the possibility that a human is injured trying to intervene, and such injury can be quite severe.)

2.  Go to the AKC site for Wheaton Terriers and look for a rescue person associated with the club in your area to place the OLDER dog who has NO visible problem behaviors that you report.  Because this breed is produced so heavily by puppy mills, you may not succeed in finding a bona fide rescue person.  But, it's well worth the effort.  Approach the Humane Society (NOT the municipal kill shelter!) and see if they are willing to evaluate the dog for the purpose of taking her for re-homing.  

Meanwhile: allowing PREY DRIVE INTERACTION IS NOT PERMISSIBLE.  NONE of these dogs should be in any situation where they are "chasing" anything, nor should they be competing in any way for attention, toys, treats, etc.  

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Jill Connor, Ph.D.


I have spent my entire professional life rehabilitating the behavior of the domestic dog and I can answer any question regarding any behavior problem in any breed dog. I have answered more than 5,000 QUESTIONS on this site in the past (almost) eight years. If you are a caring, committed owner and need advice, I'm here for you. I am personally acquainted with my colleagues (Turid Rugaas, Ian Dunbar, etc.) who were members of an elite group in EGroups that I founded: K9Shrinks. THERE ARE NO QUICK FIXES for serious behavioral issues; not only is it unprofessional to offer same, it is also unethical. IF I ASK YOU SUBSEQUENT QUESTIONS, I NEED YOU TO INTERACT WITH ME. More information equals more credible answers and a more successful outcome. If you want ANSWERS THAT WORK, participate in any way I request. I'm quite committed to working on this site for YOUR benefit and the benefit of YOUR DOG. Help me in any way you can.


30 years of solving serious behavior problems in domestic dogs; expert in dog to human aggression; Internet columnist for for 5 years; former radio talk show host, WHPC.FM, Garden City, NY "Bite Back" (1995 through 2000). List owner, international animal behavior experts, Seminar leader: "Operant Conditioning and Learning"; "Aggression in The Domestic Dog"; "Solving Problem Behaviors" -- conducted for various training facilities on Long Island from 1993 through 2000. Former clinical director of "Behavioral Abnormalities" in conjunction with Mark Beckerman, DVM, Hempstead, New York.

Member, APDT (UK); Psychologists in Ethical Treatment with Animals

Harcourt Brace Learning Direct: "The Business of Dog Training" "The Fail Safe Dog: Brain Training, not Pain Training"

Ph.D., UC Berkeley

Past/Present Clients
Board of Directors: Northeast Dog Rescue Connection; The Dog Project; Sav-A-Dog Foundation; etc. Pro Bono counselor: Little Shelter Humane Society My practice is presently limited to forensics. I diagnose cause of dog bite, based upon testimony before the Court, for attorneys and insurance companies litigating dog bites, including fatal injuries. I also do pro bono work for bona fide rescue organizations, humane societies, et al, regarding such analysis in an effort to obtain release for dogs being held for death in municipal shelters in the US.

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