I'm in desperate need of help! I have a 12 week old Lab puppy and he's showing aggressive tendancies. He's very possesive over certain toys, growling and snapping when we try to take them away. Needless to say these toys have been taken away from him permanently, even more worrying is he has now started to growl and snap when we try to stroke him! I have 2 children aged 13 & 11 who are now starting to avoid him.

Hi guest
The first thing you need to do is take your puppy to the vet for a full examination to make sure there it is not pain or discomfort causing him to snap.
I would suggest you take your puppy to a traing/socialisation class where they can advise you.
Try to work on positive play with your puppy praising him when he is good and insist on taking his toys off him with out being unkind then let him have them straight back as his reward if he snaps a very firm NO and remove him from the situation so he learns that nipping means the end of play!
Try to discourage the children from winding him up over excited puppies often nip
I would be slightly more concerned over the snapping when you stroke him but without seeing what is happening it is hard to judge
Could he just be playing?
Also have you contacted his breeder ?
if she/he is local maybe she/he could give you some practical advice?

When you go to stroke a puppy and your hand looms over its head, it will try to grab that hand. It can't see what you are going to do and panics. Try stroking from below eye height, around the shoulder area or the chest. You may get a more favourable response, with time and gentle practice. Not all puppies like to be molly-coddled though, especially if they are tired. HTH.

This is such a common problem, but not a problem. Your pup is just treating you like one of his brothers or sister and wants to be boss.

All it takes is firm no, lots of praise when he gives up his toys. You even get hold of him by the neck, just like his mum would, quick firm shake, while telling him no. He will quite probably grumble at first, this is normal, another quick shake, he might yelp, let go as soon as he stops lots of praise and good boy.

This problem is often put on our notice board, you are not the only one that has it happen, nearly everyone with a pup gets the problem.