Golden Retriever Biting

Question
Hi,

My family adopted a Golden Retriever pup exactly 3 weeks ago and everything has been going splendid up until a couple days ago. He has been quite fond of everyone but then the other day he started to growl at my 4 year old daughter when she'd sit down to pet or hug him. Yesterday he got a hold of one of her toys and she took it away. He lunged at her, growling and bit her hand. I saw it in the act and grabbed him by the collar and held him still and firmly said No. Now he did the exact same thing to my 3 year old today. He has not bit me even once. He listens to me quite well and has quickly learned sit, shake, drop it ,lay down and come here. I am concerned that this seems to be aggresion as oppose to play biting. I understand children need not disturb the pup when napping and eating however I don't think he should be biting like that when a toy is being taken away, particularly one that is not his. As I said, he was adopted so I know nothing about his parents. He's 14 weeks now and was rescued from a puppy mill. Would you recommend calling in a obedience trainer at this point?

Answer
I think if calling in a trainer will give you guidance and comfort, then the puppy is certainly not too young to benefit.

Golden retrievers are "oral" dogs; that's why they retrieve.  ALL dogs use their mouths like we use our hands.  I don't really feel what you're dealing with is aggression, just lack of rules and boundaries.  He's only a baby, and he doesn't know the difference between his toys and anyone else's.  This is something you have to teach him.  Most dogs will think anything on the floor is fair game, unless they've been taught otherwise.

Here's a bunch of puppy-related information, plus some general information on helping the entire family let the dog know in a benevolent way who's the leader and who's the dog.

http://www.hsmo.org/m_obedience/puppyissues.swf
http://www.hsmo.org/m_obedience/behavior/puptrain.html
http://www.hsmo.org/m_obedience/behavior/pupnip.html
http://www.hsmo.org/m_obedience/behavior/pupstage.html
http://www.hsmo.org/m_obedience/behavior/pupchew.html
http://www.marinhumanesociety.org/Behavior/Handouts/PuppyStuff.pdf
http://www.ddfl.org/behavior/kidsdogs.pdf
http://www.ddfl.org/behavior/dogbite_guide.pdf

http://www.marinhumanesociety.org/Behavior/Handouts/PEP.pdf
http://www.ddfl.org/behavior/nilif.pdf
http://www.ddfl.org/behavior/educated-dog.pdf