Yes, babies need to see the full range of emotions and how to express them safely and appropriately. Masking our emotions is helpful when we don’t trust ourselves to show how we feel in an appropriate way, but for the most part, children should know that feeling sad is okay and that they can express their sadness without fearing punishment or judgment. Parents set the stage for their child’s healthy emotional expression by showing their own emotions, even negative feelings like sadness and frustration. You can also use negative feelings to show your child how to recover their more positive moods, too, by modeling coping skills yourself and talking about coping as your child gets older.
– See more at: http://purplecrying.info/sub-pages/protecting/commonly-asked-questions.php#sthash.zoh8gNRY.dpuf