A month ago my sister gave birth to a baby boy and our dog, Toffee, has been acting very strange ever since. He's growled at different members of the family multiple times, usually for moving him off of my sister or for punishing him. I can't figure out why he's being so mean to everyone.
Also two days ago he growled at me for trying to move him off my sister. I've always been very gentle and easy going with him, but I was much firmer than I usually am with him telling him that was bad and not calling him like 5 seconds later (I took about a minute instead) to show love. But when I called him this time, he was shaking in my lap like he was scared, and growled at me again. Now he runs and hides every time he sees me, and he growls whenever I try to pet him. I don't know what I did wrong but I'm so scared; I love this dog deeply and I really want things to be okay again. He also has a history of being abused before we got him, and I don't know if that factors into this.