Lie Detector 
A lie detector in a dream represents a test which you are trying to pass. You may have a secret which is bothering you and you are afraid of being caught. You may also have a big interview ahead, or a final exam, which is causing you stress.
Sister In Law
To dream of your sister-in-law symbolizes attributes that the both of you may have in common. Also, contemplate the bond that you both share. If you are arguing with your sister-in-law, it may imply that you refuse to accept that you both have certain aspects or attributes in common.
Brother-In-Law
If you dream of your actual brother-in-law, consider the situation and the circumstances in the dream. This dream has more to do with every details such as occurrences and events than a visual image of your brother-in-law.
If you currently don't have a brother-in-law but dream that you do or you're the one, it symbolizes your search for family and acceptance.