I have a four year old Black and White male Border Collie named Rocket. He's been my boy ( mommy's boy) his whole life. The day I left for college and had to leave him at my mom's his behavior /attitude changed. While I was home if the neighbor was target practicing or their was a thunderstorm he slept peaceful on my bed curled up next to me on behind his favorite couch. I went to my mom's a couple weeks ago and she told me that either I take my dog with me or she's getting him tranquilized so he's "more mellow". I spent the night at my mom's because there were tornado watches out and my sister went to go touch Rocket while he was laying at my feet and he nipped her. I scolded him and then left him downstairs ,to go to bed. I got up in the middle of the night to check on him and I did the same thing my sister did. He did nothing but lick my hand........... What's going on with my baby boy?? He's now staying with me and my husband at his grandma's farm and he's back to being an angel. I don't understand why he was acting the way he was. Does anyone have any ideas?