Very disturbing behavior

Question
Dylan is a very sweet, non-aggressive, obedient, mild-mannered 9 1/2 month old, non-neutered, male lab.  We also have Jake, who is Dylan's 2 year-old neutered brother (from another mother...same dad).
Dylan is always loving and calm except when he is in our swimming pool with other people.  He becomes aggressive (not growling or snarling aggressive) but he swims with intent toward our kids (teenagers)and swats them with his paws and mouth.  What is going on here?  My husband is afraid the dog has aggressive tendencies.  The dog is completely normal in every other situation. Help me understand what is happening here so that I can correct it. With neutering help, also?

Answer
That is disturbing.  It sounds like that is how he thinks he should play in the water.  Neutering may help, and it would be best for many other reasons if you went ahead.  A good obedience program would help. The key to most behavior problems is approaching things using the dog's natural instincts. Dogs see all the people and dogs in the household as a pack with each having their own rank in the pack and a top dog. Life is much easier if the 2 legged pack members outrank the 4 legged ones. You can learn to play the role of top dog by reading some books or going to a good obedience class. A good obedience class or book is about you being top dog, not about rewarding standard commands with a treat. Start at http://www.dogsbestfriend.com/ For more on being top dog, see http://www.dogbreedinfo.com./topdogrules.htm

Denial of attention as with other problems may help too.  Every time he swats anybody, they yelp and leave.  If he plays nice, he has company in the pool.  It should be very effective with an attention loving golden.