Hello! I've a 12-week old Silver Lab called Cosmo. Generally he's doing ... ok. Training is difficult but he's got basic commands down (when he feels like it). Our main issue is one of biting. I know all puppies go through this stage, but I am concerned about 2 things: 1. When our 9-year old son is on the sofa, Cosmo will really go for him. He tries to get his feet or whatever he's holding, and the biting doesn't feel playful. Cosmo is not allowed on the sofa (note: he was, but we found he was being too bitey with everyone else so felt he was trying to take it over), so perhaps it is something to do with the fact that he see's our son as 'similar' to him, and therefore is jealous? 2. Cosmo today tried to get up the stairs - I removed him (as he was stuck) and when I put him down he starting biting my legs hard and growling. I felt bad, but the only thing I could do was take him by the collar and put him in his pen. I know this is probably a bad thing to do, but simply walking away wasn't an option (it's hard when he's got hold of your leg!) So ... is this normal? Or at least can people relate? I am hoping once we can take him out for proper walks in a few days time this might help. But my wife and I are a little concerned that this feels more aggressive than it should? Maybe that's not the case ... so any advice, tips or just general reassurance would be great! Thanks!