Our third golden was like that with my son. My son was only 3 months and she was only 8 months old when we got her. They grew up together and even in her old age would run to the fence line when she heard the school bus to wait for him. She was very hard to loose for all of us,but even harder for my son. But he must have something with Goldens because Summer is just as attached to him, she will leave anyone or anything to greet him when she hears him coming home!