aggressive

Question
Can dogs that are aggressive change? We have a 1 yr old Chesapeake Bay,1/4 lab,1/4 shepherd not nurtured. Very possessive,jealous,over people other dogs male or female,dog toys. Has not bite a person so far just growls,just likes to fight w/ other dogs so far!  Yesterday our 4 yr old child was on the slide playing at the bottom,got off then he went over and lifted his leg.

Answer
Questions:
1.  What do you mean by "not nurtured"?
2.  How do you know the genetic makeup of this dog?
3.  How does the dog demonstrate possessive aggression over people?
4.  When did he start growling, under what circumstances, at what age?
5.  What sort of training have you done?
6.  How did you socialize this dog to people and other dogs, at what age did you begin, and under what circumstances?
7.  Does the dog direct growls at people: who, and when?
8.  What do you DO when the dog growls?
9.  Do you have other dogs in the household, how many, what ages/sex?
10. How many people are in your household, including children and their age(s)?
11. How does the dog greet visitors to your home?
12. Is the dog neutered? What is the dog's history of veterinary visits (vaccinations, orthopedic evaluation)?

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