the same thing happens with my cocker spaniel. everytime we have guests he HAS to be the center of attention. i solved it with a treat. everytime we have guests i take couple of treats and make him sit next to me,then give him treats until he calms down. its a blast of explosion. he is with me all the time, so i don't think the problem is you not being home as much as your sister. when i was living with my parents , it was the same thing. its just a center of attention problem. at least with Grumpy. And yes,. he growls "LOOK AT ME", too, especially to my boyfriend and yawns really loud, his docked tail waves like crazy and his butt is in the air. not to mention he ADORES being between legs while you try to walk,keep balance and try not to step on him. Snowflake is different, every move he makes is "LOOK AT ME" while Grumpy is just plain i wanna be the center of attention dog. hope i helped.