hi my name is larane i have had dogs all my life but have never had a pup that as shown aggression i may add this is anew thing...let me tell you about my new girl skye she is 18 weeks border collie cross we got her at 8 weeks and has grown drastically she now weighs 20lbs but is very lean at the back end and muscular at chest skye has been doing good walks to heel chances her arm_or paw in her case but for past two weeks when my 18 year old daughter leans down toher we hear growling and she shows her teeth its also happened to my husband and this evening she did same to myself she was severely reprimanded verbally and ignored and she took herself into her crate she came back out about 10 mins later and has been her usual charming self whats going on and am i dealing with it in the right way she has also started barking when door is knocked .phone rings or meeting strangers while out walking mainly at night