Rejecting a visitor??

Does anyone's baby reject a specific family member or any type of guest who comes into your home? I cannot seem to figure it out, but my 5wk old daughter is rejecting my inlaws like the plague. I have her on a great schedule and I accept visitors after 11:30/12pm which is her best time between 12 and 3pm. Everyone that comes through the front door has been following these simple guidelines and have a great experience with her. She is always up, alert, and happy looking around with excitement....except them. She is an extreme fussball -- it's not gas, it's not a feeding time, her diaper is always clean...I just feel terrible that they have not been able to enjoy her like others have including myself and my husband. Do you think it's a certain scent on them coming from home? Is it their dog? Are they just not handling her correctly? Can she sense something from them that we adults don't? Idk I'm confused. Just looking to see if anyone else has had this happen to their family members before.