My 9 month old puppy has suddenly started barking and growling at people. She did it for the first time today for no reason. The person not child was no where near her. I instantly corrected her with a little tug on her leash and stepped in front of her to block her view. She was told to leave it and I gave her a treat once she had sat quietly for a minute or so. But as soon as she saw the child and person again, same reaction. I ended up removing her from the situation before it escalated further. It’s not her normal bark, it’s a lot deeper and she sounds almost aggressive. I don’t want this behaviour to continue as she gets older. It’s not her first time seeing this child or person either. She’s been around kids all her life. I like to say she is well socialised. How do I stop this behaviour? I’m not sure if what I did was right or wrong! She’s a malamute x staff so she’s not exactly small either!