You’re not fooling anyone with that fake smile, not even a baby. New research finds that children as young as 18 months can tell when a parent is lying. Canadian researchers tested this by having participants between 15 and 18 months old watch an actor go through several scenarios. With each scenario the actor gave the appropriate response or the opposite reaction expected. Researchers say the 18-month-old babies knew when the actor’s facial expression did not match what was happening, and that the toddlers showed empathy towards the actor only when they knew his sad face was justified.

Researchers say, “Adults often try to shield infants from distress by putting on a happy face following a negative experience. But babies know the truth: as early as 18 months, they can implicitly understand which emotions go with which events.”(Daily Mail)