My name is Bucky!

We rescued Bucky from a shelter in Florida 2 years ago. My 3yo son & wife wanted a puppy but the circumstances of our busy life didn't allow for that kind of addition. So I was happy to give Bucky a happy ending to his journey. Since the day we got him his been a grateful, loving lap dog who doesn't really need much as his age makes him sorta lazy. He still gets the zoomies & loves to wrestle on occasion. He never gave us any trouble with my son, or other pets/local dogs. He is rather unbothered by just about everything. His favorite things are Rollin around in the grass & car rides too. Now, my family has grown and we have 2 boys. When we adopted Bucky, he was the dream dog that checked every companion box my family wanted in a puppy. He is house broken & latched to us very quickly. But ever since we had my 2nd son, his attitude has changed entirely. I cant tell if he is scared or angry but he is extremely hostile to my infant. Snarls and bites at him, only him.