I have Flik, an 11yo, 11lb Maltese that I've had for 10 years. He was reactive at first, but through extensive DIY training (like YEARS of watching videos and reading), I was finally able to turn my tiny menace into a mostly respectable member of dog society.
I frequently go to my parent's house and they have Finn, a 4yo, 24lb Havanese mix that they've had for about 3 years and Ember, a 1.5 yo, 65lb Chow/Collie mix they've had for about 5 months. Both are good dogs, but Finn is a little timid, especially around those he's unfamiliar with. Meanwhile, Ember is just an unproblematic angel and just happy to be included in whatever is going on.
In the past years, Flik has always been pretty dominant at the house, but not aggressive, with Finn. He's generally good with other dogs, just not fond of people, but in the last 2-3 months, Finn has been getting really excessively rough with Flik.
Finn's attacks started out mild at first, just low growls and glaring, which we would always immediately scold him for, but this weekend, I am sitting on the couch talking to my mom and Finn suddenly charges from across the room at Flik. I yelled at him to stop his charge and backed him away from Flik. Luckily, he was unharmed. He did it again later the same day and this time, Flik yelped as Finn grabbed the back of his neck. I again yelled at him to stop and he immediately let go, but I just don't know why he would be doing this in the first place? Flik was ignoring him and not doing anything at all to provoke Finn, yet Finn rushed him.
I just need help maybe understanding why this might be happening because it just doesn't make sense in my mind. Any advice on how to handle the dogs or help train my parents on what to do would be greatly appreciated!